General MacArthur decides not to go all the way to the Yalu River

[oscssw]

Mac decides to play it safe and provide for the possibility Mao would intervene by halting the UN advance in the very best defensive ground in Korea.  MacArthur halts his troops at Korea's narrow neck – around 100 miles wide and 100 miles  south of the Yalu River. This would have left the UN forces with 90 percent of the Korean population and Pyongyang.  Winston Churchill, urged this on MacArthur. The DMZ could have been proposed between this line and the Yalu River.

By doing this  Mac would have avoided a 400-mile wide border and would have been able to engage the ChiComs on  excellent defensive ground that would allow his maximum use of his superior armor, firepower and air power.  He would also not have split his army into two separated forces one on the west the other on the east with mountains between them that denied them mutual support. Once the ChiComs are stopped the UN control of the air and sea would allow Mac's amphibious genius to land blocking troops behind the stalled, starving and eviscerated Chicom forces to conduct joint ops with his armor heavy land forces.  Does Mac pull off another Cannae?

What does Mao do?  Negotiated settlement or send his, mainly light infantry armies, into a meat grinder with all the advantages on the side of the UN?

Does Mac Defeat Truman and how would a Mac administration differ from Ike's?

What are the ramifications of a real WIN in Korea for the cold war?

Would the US be more likely to go all in to support the French in Indo China?

Does the rift between the PRC and the Soviet Union happen earlier and more venomous because Joe Stalin refused Mao's request for direct support OTL until his troops showed they could push back the UN?   Or, seeing the defeat of it's Communist brother, Stalin now authorized direct involvement of the Red Army/Airforce in a renewed attack south?

    

[lordroel]

Feb 14, 2021 15:07:42 GMT oscssw said:

Mac decides to play it safe and provide for the possibility Mao would intervene by halting the UN advance in the very best defensive ground in Korea. 

MacArthur playing it safe, that is new, he wanted to drop nukes on China, playing it safe is not something i think is in his dictionary. 

[gillan1220]

I think the Chinese would still intervene due to fears of a U.S.-led invasion.

[lordroel]

Feb 14, 2021 16:39:07 GMT gillan1220 said:

I think the Chinese would still intervene due to fears of a U.S.-led invasion.

But they will with the North Koreans most likely run up against a United States defensive line, if that line will hold is a different question.

[gillan1220]

Feb 14, 2021 16:40:45 GMT lordroel said:

Feb 14, 2021 16:39:07 GMT gillan1220 said:

I think the Chinese would still intervene due to fears of a U.S.-led invasion.

But they will with the North Koreans most likely run up against a United States defensive line, if that line will hold is a different question.

For it to survive, the KPA must receive support from China and the Soviet Union when engaging this U.S.-led UN defensive line.

[oscssw]

Feb 14, 2021 16:40:45 GMT lordroel said:

Feb 14, 2021 16:39:07 GMT gillan1220 said:

I think the Chinese would still intervene due to fears of a U.S.-led invasion.

But they will with the North Koreans most likely run up against a United States defensive line, if that line will hold is a different question.

The PLA in Korea was a light infantry force.   They were very weak in tanks and artillery.  They had almost zero air support.

The reason the PLA was so successful in the OTL was a divided, overextended strung out, road bound and over confident UN forces.   In my timeline the UN is Dug in a much shorter, excellent defensive position much closer to it's secure supply bases in country that would allow the use of it's much larger armored forces and more important massed artillery against troops in the open.  Artillery, which is an all weather arm, not air power dependent on weather conditions would be decisive.  

[gillan1220]

Feb 17, 2021 13:32:40 GMT oscssw said:

Feb 14, 2021 16:40:45 GMT lordroel said:

But they will with the North Koreans most likely run up against a United States defensive line, if that line will hold is a different question.

The PLA in Korea was a light infantry force.   They were very weak in tanks and artillery.  They had almost zero air support.

The reason the PLA was so successful in the OTL was a divided, overextended strung out, road bound and over confident UN forces.   In my timeline the UN is Dug in a much shorter, excellent defensive position much closer to it's secure supply bases in country that would allow the use of it's much larger armored forces and more important massed artillery against troops in the open.  Artillery, which is an all weather arm, not air power dependent on weather conditions would be decisive.  

That always baffles me how come a mightier UN force got rerouted all the way to the 38th Parallel when they all had armor, artillery, air, and naval support.

[oscssw]

Feb 17, 2021 15:05:20 GMT gillan1220 said:

Feb 17, 2021 13:32:40 GMT oscssw said:

The PLA in Korea was a light infantry force.   They were very weak in tanks and artillery.  They had almost zero air support.

The reason the PLA was so successful in the OTL was a divided, overextended strung out, road bound and over confident UN forces.   In my timeline the UN is Dug in a much shorter, excellent defensive position much closer to it's secure supply bases in country that would allow the use of it's much larger armored forces and more important massed artillery against troops in the open.  Artillery, which is an all weather arm, not air power dependent on weather conditions would be decisive.  

That always baffles me how come a mightier UN force got rerouted all the way to the 38th Parallel when they all had armor, artillery, air, and naval support.

That Gillan is a very good question.  

To sum it up briefly The reason the PLA was so successful in the OTL was a divided, overextended strung out, road bound and over confident UN forces and Mac was totally responsible for this disaster.   I have read many first hand accounts.   They indicate Mac and, in the opinion of many (myself included), his Intel folks really blew it.  In fact, it was the worse kind of unprofessionalism not to thoroughly investigate intel that did not support El Supremo's  preconceived opinion.  

This is not pretty but it pretty well sums up the failure.  This is from the Brookings Instute Article

Catastrophe on the Yalu: America’s intelligence failure in Korea
By Bruce Riedel September 13, 2017

The full article, which is quite long but well worth reading, can be found at.

www.brookings.edu/blog/order-from-chaos/2017/09/13/catastrophe-on-the-yalu-americas-intelligence-failure-in-korea/

   .   .   .

"MacArthur had always understood that if you “control intelligence, you control decision making.” He had built an intelligence community in his area of command that listened attentively to what he wanted and gave him intelligence that reinforced his already held views. MacArthur wanted total control of the war and its execution, not second-guessing by his subordinates or outside interference by Washington, especially by the White House and the Pentagon. If his Tokyo command headquarters were solely responsible for collecting and assessing intelligence on the enemy, then MacArthur alone could decide how big the enemy threat was and thus what to do about it.

MacArthur’s intelligence chief, or G2, was General Charles Willoughby.

In June 1950 Willoughby assured MacArthur that North Korea would not invade the South, despite
alarms raised by then-CIA director Admiral Roscoe Hillenkoetter. In the fall of that year Willoughby’s office refused to believe or confirm reports that thousands of CCF troops were in North Korea. Even when Chinese prisoners were captured, Willoughby dismissed them as a few experts or advisers, not as group of soldiers. The G2 in Tokyo recognized that some Chinese divisions had entered the North, but argued that they were not full-strength combat units. Willoughby “
doctored the intelligence in order to permit MacArthur’s forces to go where they wanted to go militarily, to the banks of the Yalu,” with no contrary or dissenting voices heard in Tokyo or Washington. The Tokyo estimate of the number of CCF forces in Korea was less than one-tenth the reality.

   .    .    .

"The Yalu disaster was completely predictable. The intelligence failure was the result of a policy maker’s determination that intelligence support his preconceived views, not challenge them. It is a timeless lesson."

[lordroel]

Feb 17, 2021 15:05:20 GMT gillan1220 said:

Feb 17, 2021 13:32:40 GMT oscssw said:

The PLA in Korea was a light infantry force.   They were very weak in tanks and artillery.  They had almost zero air support.

The reason the PLA was so successful in the OTL was a divided, overextended strung out, road bound and over confident UN forces.   In my timeline the UN is Dug in a much shorter, excellent defensive position much closer to it's secure supply bases in country that would allow the use of it's much larger armored forces and more important massed artillery against troops in the open.  Artillery, which is an all weather arm, not air power dependent on weather conditions would be decisive.  

That always baffles me how come a mightier UN force got rerouted all the way to the 38th Parallel when they all had armor, artillery, air, and naval support.

Could it be that there where more Chinese volunteers then what the UN armor, artillery, air, and naval support could handle.

[James G]

Feb 17, 2021 13:32:40 GMT oscssw said:

Feb 14, 2021 16:40:45 GMT lordroel said:

But they will with the North Koreans most likely run up against a United States defensive line, if that line will hold is a different question.

The PLA in Korea was a light infantry force.   They were very weak in tanks and artillery.  They had almost zero air support.

The reason the PLA was so successful in the OTL was a divided, overextended strung out, road bound and over confident UN forces.   In my timeline the UN is Dug in a much shorter, excellent defensive position much closer to it's secure supply bases in country that would allow the use of it's much larger armored forces and more important massed artillery against troops in the open.  Artillery, which is an all weather arm, not air power dependent on weather conditions would be decisive.  

Just thinking here - and could be wrong - but if this had happened and the defensive line held, there would be no future Inchon Landing. Could that have done it in for the US Marines? IIRC, there was serious post-WW2 talk of getting rid of the US Marines but the Inchon landing changed minds there.

[La Rouge Beret]

IIRC couldn't Mac have stopped right before the Pyongyang or was it just north of there and consolidated his forces? If I remember there was a mountain range that could have acted as a natural defensive position, either way the decision to over extend his forces was a mistake as was expecting that Communist China would not seek to preserve at least part of a buffer state.

[simon darkshade]

Inchon happened before the offensive into North Korea.

Holding on the “neck of Korea” would lessen the frontage that had to be manned by ROK troops somewhat, but not eliminate it; not having a separation of X Corps and Eighth Army helps. It just needs a completely different commander.

MacArthur could have ordered such a halt, but would need substantial changes in his character to do so. When reports of the Chinese strength in North Korea reached his staff, they were played down and discredited. The aim was total victory and to release troops for home and Europe.

As an additional note, the PLA had a habit of trying to get within the coverage of artillery, to “grasp the enemy’s belt”. This would lead to success in areas not covered in as much depth by US artillery, particularly ROK positions and in the centre of the peninsula. I’d also say it would take time to build up the logistical infrastructure up to the Neck of Korea, given the damage done by US airpower on what was already a pretty parlous network. It wouldn’t be on the level of that of South Korea leading up to the Han and the border. Inchon/Seoul was not repaired fast enough to take the volume of supplies and materiel needed for a full attritional battle up north, so there would be a number of bottlenecks. One of the big reasons for X Corps’s landings on the east coast was to grab a port for the flow of supplies.

Overall, it wouldn’t be impossible, but would need changes in Mac, how he ran his staff and how they ran him and the logistical net of Central Korea.

[oscssw]

Feb 17, 2021 17:47:14 GMT James G said:

Feb 17, 2021 13:32:40 GMT oscssw said:

The PLA in Korea was a light infantry force.   They were very weak in tanks and artillery.  They had almost zero air support.

The reason the PLA was so successful in the OTL was a divided, overextended strung out, road bound and over confident UN forces.   In my timeline the UN is Dug in a much shorter, excellent defensive position much closer to it's secure supply bases in country that would allow the use of it's much larger armored forces and more important massed artillery against troops in the open.  Artillery, which is an all weather arm, not air power dependent on weather conditions would be decisive.  

Just thinking here - and could be wrong - but if this had happened and the defensive line held, there would be no future Inchon Landing. Could that have done it in for the US Marines? IIRC, there was serious post-WW2 talk of getting rid of the US Marines but the Inchon landing changed minds there.

Inchon landing was on Sept 15, 1950 so it had already happened before the UN took Seoul and went north of the 38th parallel. That predates this defensive alternate time tine.

[James G]

Feb 18, 2021 11:03:15 GMT oscssw said:

Feb 17, 2021 17:47:14 GMT James G said:

Just thinking here - and could be wrong - but if this had happened and the defensive line held, there would be no future Inchon Landing. Could that have done it in for the US Marines? IIRC, there was serious post-WW2 talk of getting rid of the US Marines but the Inchon landing changed minds there.

Inchon landing was on Sept 15, 1950 so it had already happened before the UN took Seoul and went north of the 38th parallel. That predates this defensive alternate time tine.

My mistake.

[stevep]

Feb 17, 2021 16:43:04 GMT oscssw said:

Feb 17, 2021 15:05:20 GMT gillan1220 said:

That always baffles me how come a mightier UN force got rerouted all the way to the 38th Parallel when they all had armor, artillery, air, and naval support.

That Gillan is a very good question.  

To sum it up briefly The reason the PLA was so successful in the OTL was a divided, overextended strung out, road bound and over confident UN forces and Mac was totally responsible for this disaster.   I have read many first hand accounts.   They indicate Mac and, in the opinion of many (myself included), his Intel folks really blew it.  In fact, it was the worse kind of unprofessionalism not to thoroughly investigate intel that did not support El Supremo's  preconceived opinion.  

This is not pretty but it pretty well sums up the failure.  This is from the Brookings Instute Article

Catastrophe on the Yalu: America’s intelligence failure in Korea
By Bruce Riedel September 13, 2017

The full article, which is quite long but well worth reading, can be found at.

www.brookings.edu/blog/order-from-chaos/2017/09/13/catastrophe-on-the-yalu-americas-intelligence-failure-in-korea/

   .   .   .

"MacArthur had always understood that if you “control intelligence, you control decision making.” He had built an intelligence community in his area of command that listened attentively to what he wanted and gave him intelligence that reinforced his already held views. MacArthur wanted total control of the war and its execution, not second-guessing by his subordinates or outside interference by Washington, especially by the White House and the Pentagon. If his Tokyo command headquarters were solely responsible for collecting and assessing intelligence on the enemy, then MacArthur alone could decide how big the enemy threat was and thus what to do about it.

MacArthur’s intelligence chief, or G2, was General Charles Willoughby.

In June 1950 Willoughby assured MacArthur that North Korea would not invade the South, despite
alarms raised by then-CIA director Admiral Roscoe Hillenkoetter. In the fall of that year Willoughby’s office refused to believe or confirm reports that thousands of CCF troops were in North Korea. Even when Chinese prisoners were captured, Willoughby dismissed them as a few experts or advisers, not as group of soldiers. The G2 in Tokyo recognized that some Chinese divisions had entered the North, but argued that they were not full-strength combat units. Willoughby “
doctored the intelligence in order to permit MacArthur’s forces to go where they wanted to go militarily, to the banks of the Yalu,” with no contrary or dissenting voices heard in Tokyo or Washington. The Tokyo estimate of the number of CCF forces in Korea was less than one-tenth the reality.

   .    .    .

"The Yalu disaster was completely predictable. The intelligence failure was the result of a policy maker’s determination that intelligence support his preconceived views, not challenge them. It is a timeless lesson."

  oscssw,

  Interesting and depressing condemnation of MacArthur and his mode of operation.   Sounds like a very good job that Truman later fired him and his plans for political office came to nothing.

  It seems that Mao committed himself to Chinese intervention once the Inchon landing prompted the collapse of the NK forces.  As such your still going to get attacks and given the coming winter, which the UN forces didn't seem fully prepared for plus the terrain and logistical issues you mentioned would have caused them problems but if MacArthur wasn't such an idiot it would have been markedly better for the UN forces and worse for the communists.  The latter would have continued upping the ante I suspect and forced the defenders back some way but I suspect you might have avoided the 2nd occupation of Seoul and made a bigger imbalance in the losses of the two sides than OTL.  Probably a shorter shooting war as well and perhaps SK being somewhat larger, which would make the capital more secure.