Why didn't the USA move to the left after WWII?

There was a lot of left in America during those years. I'm skipping some countries, but I'm sure you can read something about the left in America over here and here.

Edit: Question title changed, answer no more valid. Thanks for correcting!

The share of government spending in GDP is mainly correlated with growth of the service sector and urbanization. In agrarian societies, people are independent and can live off the land. As countries develop people become more dependent on government.

In the US urbanization was a bit slower, hence, the slower spending growth.

I wasn't able to read all of the comments above - but am sure someone has mentioned the dichotomy between statism and anarchy/libertarianism. Global governments desired more control post-WWII (including the United States) but the people were oftentimes more inclined to give it in affluent Europe or nations undergoing an industrial revolution such as those in Central or South America.

Many in the U.S., at least identify with the idea of limited government more than their European counterparts - certainly in regards to economics. We've seen this play out significantly over the past 50 years.

The main difference between the totalitarian states in the 1900s and the democracies was not at all in economic policy but in to what extent and to what detail the (federal) state was allowed to rule over citizens (private) lives by using force.

The bipolar left-right economical spectrum did not at all take authoritarian / personal liberty into account.

"Extreme left" and "extreme right" did not mean extremely much to the left or extremely much to the right. It meant "economically left But with extremely little personal freedom" and "economically right But with extremely little personal freedom".

This is a great question, and I've decided to write my own answer since the existing ones fail to mention a few facts.

1. Reason #1 should be J. Edgar Hoover. Even before Truman's creating the 'national security state', the FBI succeeded in infiltrating the communist party and most left-wing organizations. Out of each four communist party card-carrying members, three were FBI informants. The 'left' field was completely and utterly compromised.

2. The unions, unlike their European counterparts, were averse to communist propaganda. Some union leaders used to be 'fellow travelers' in the 1930s but the purges, the Winter War, and the Molotow-Ribbentrop Pact quickly changed their minds (cf. the case of Walter Reuther who was instrumental in getting rid of pink colors in the UAW membership). The unions were quite influential, and members of the New Deal coalition.

3. Harry Truman gathered various conservative, wealthy, East Coast-educated, Georgetown-dining gentlemen in the national security apparatus. This machine worked efficiently to protect itself and the American state from subversion, i.a. by allying with and indirectly controlling mainstream media outlets (see the Alsop brothers, for instance). It also expended much effort and money to subvert European communist parties, to set up 'stay behind' shadow state, to train law enforcement and special services there...

4. Stalin had his hands full and naturally devoted more attention to the events in Europe.

5. The United States quickly climbed out of shallow post-war economic depression and surged forward. Whatever rationing there was was quickly abolished. A full belly would not harbor treasonous thoughts.

Your question operates from a very black and white view of left/right, and your mistaken assumption is that the Nazis were of the political right.

The Nazis were Nationalist Socialists and often leaned left. Their fight against the Soviets weren't because they were opposed to Communism. Remember that Hitler allied with Stalin and then double crossed him so there wasn't a lot of ideology going on there.

"Liberal Facism" by Jonah Goldberg outlines in great detail how the Nazis had more in common with traditional leftism than American conservatism.

In order to discuss this sensibly, it's necessary to distinguish the social-democrat left from the actual Communist left. "Fabian" socialism as opposed to revolutionary Marxism. The former pursued economic redistribution, the establishment of public healthcare and education systems, and nationalisation of some industries while generally leaving private property alone and retaining elections. The latter didn't, and were often thoroughly infiltrated by actual Stalinists and KGB agents. Although not as thoroughly as Joe McCarthy would have you believe.

Another key point is that European countries became command economies (or at least heavily requisitioned economies) as soon as the war started. Non-state economic activity became very difficult due to lack of resources and manpower, while a huge state economy was built to produce war materiel and ration everything else.

Let's also not understate how much was destroyed, and how many people were killed, exiled, expropriated, wounded or seriously inconvenienced by the war. It was a war of indiscriminate destruction from the air. A significant fraction of Europe's remaining traditional hereditary aristocracy were killed, in some cases wiping out entire family lines.

The existing social and economic order was simply blown to pieces, a lot needed to be (re)built, and everyone was already mobilised. It's a short step from state-directed building of aircraft, hospitals and barracks to state-directed building of cars, hospitals and houses.

America suffered no such destruction of property, providing less of an opportunity to redistribute its replacement. Meanwhile the foundations for post-war technological industries were being built around the arms manufacturers, and the post-war space race.

There were a lot of public left/right confrontations in various countries in the 60s. Everything from the US civil rights movement to the soixante-huitards to the Greek internal conflict which collapsed into a military dictatorship. Italy could have gone either way (and the CIA were involved there, in Operation Gladio). Also de-colonialisation by France and the UK; arguably this is a shift to the "left".

It's also important to look at how pivotal individual figures were and how differently things could have gone if, say, JFK and MLK hadn't been assasinated. The US could have ended up not so far to the right.

But ultimately a lot of the US "rightism" was straightforward power politics of anti-communism, competing against the Soviet Union. This included sponsoring terrorism and coups in South America, the Vietnam War, and so on.

Edit: this is a huge question, really. How much of "Europe" are you counting? France+Benelux+West Germany+Scandinavia+Italy count as "left", I suppose, but what about military dictatorships in Spain+Portugal+Greece?

About bomb damage in the UK: while this only affected a small fraction of buildings, it was an omnipresent threat in any urban area. The British victory is seen in popular history as fundamentally collective - "pulling together", "blitz spirit", Dunkirk's "little ships", rationing, etc. (Slightly contradicted by talking about "the few" of the air superiority fighters and the aristocratic flavour of the RAF, though).

America lacks universal health care partly because of a persistent popular belieft that ill-health reflects immorality, while the UK set its up at a time (1944) when anyone could be injured by shrapnel at any time without it being a reflection on their character.

Compared to when?

If you look at the USA politically in 1946 vs 1939 you see a very different shift than if you were to compare 1946 to 1926.

The Great Depression and the resulting New deal did push the USA further "left" (if you can call it that).

The thing to notice is that in this case, there was a clear compelling reason to do so - 25% of Americans were out of work in various portions of the 30s. There were clear, compelling reasons in the American mainland which drove this "jut to the left."

Contrast this to post WWII. America by and large saw economy, political, and cultural aspects work in WWII and lead America to victory. While the factors you see are true, the average American in fall 1945 would have been far more likely to see and value the success of the American system - and see strength and value in leaving it untouched.

There just was not a compelling reason for the average American to be motivated to "push America left" as you are asking about.

In occupied western Europe, underground communist parties took a large role in anti-nazi resistance, for which they were electorally rewarded. Not being occupied, the war experience in the UK and the USA was very different. Experiences in eastern Europe, where nazi terror was replaced by stalinist oppression, was different yet.

Three days from now (on 25 February), the February strike will be exactly 75 years ago. This was one of the major events in Nazi-occupied Netherlands. The strike was initiated by the underground Communist party, aiming to stop the racism against the Jews. Although it didn't last long and didn't save any Jews, it did cause major credit to the Communist party and their best-ever election result in the first post-war elections, when they received over 10% nationally (1937: 3.4%) and over 30% in Amsterdam, the centre of the strike and other communist-led resistance. Their newspaper (De Waarheid, or Truth) was very briefly the largest newspaper in The Netherlands. The support dwindled quickly when the communist party treated harshly (such as through character assassination) anyone not following the line determined centrally (from Moscow), including communists considered war resistance heroes by many. Not much support was left after the Communist Party supported the Soviet invasion of Hungary after the Hungarian revolution, when communist support in national elections fell to 2.4%. It didn't take any McCarthyism to severely damage the Party — the Dutch communists did it all to themselves/with "help" from Moscow¹.

Communists were very active in other elements of the resistance as well, in The Netherlands, France, and elsewhere.

¹^{The Dutch secret service did to its part by encouraging splits within the Communist party. To what extent they contributed to the demise of the Communist party remains up for debate.}

One reason was that America was the biggest winner of World War II. It started the war with about 40% of the world's industrial capacity (according to Paul Kennedy, the Rise and Fall of the Great Powers"), and ended with about "half" of the capacity of a war-torn world. Other countries that were on the winning side, Britain, the Soviet Union, and China, were worse off than before the war. The war weariness was most felt in Britain, where voters threw out war leader Churchill. Many people in Britain went "left" because they did not feel that the sacrifices were worth it, or that they had gotten their fair share of the spoils.

Returning American "GI" veterans were the most empowered men in the world. The GI Bill gave men from working class families the means to attend college, and later staff the managerial ranks of America's burgeoning industrial complex. Those that retained "blue" collars were still war heroes, and treated as such by unions, and managements. American workers had fewer grievances than those elsewhere, and were less likely to sympathize with "leftists."

In 1945, there were three basic political groups: liberal Democrats, conservative democrats, and (right-leaning) Republicans. Taken as a "body," the American public was quite conservative. President Franklin Delano Roosevelt was admired for his "competence," but he was actually placed in power by a conservative Texan, John Nance Garner. After FDR tried to replace Garner as Vice-President with his leftist "soul mate," Henry Wallace in 1940, the Democratic Party balked in 1944 and insisted on the more conservative Harry Truman, who (in)famously said, "“If we see that Germany is winning we ought to help Russia and if Russia is winning we ought to help Germany, and that way let them kill as many as possible, although I don't want to see Hitler victorious under any circumstances.” After he became President, Truman allied with (West) Germany and started the Cold War against the Russians. This helped lead to the "villification of "left wingers" in the United States.

"The Nazis are and were demonised as much in the US" as elsewhere. That's true only up to a point. It is important to note that through the 1950s, some people in America advocated racial policies against African-Americans that were actually "milder" versions of Nazi racial policies. Some authorities believe that Naziism was partly inspired by the American eugenics movement of the 1920s.