Please note: Even though OP is phrasing the question such that it sounds like a current events question, it is still a valid question regarding the historical context and attitudes toward communism any time before 1995.

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OP: If you could add a little more detail to your description that might help.

American disdain for communism began during the late nineteenth century as labor radicalism grew. At that time, and to this day, American culture and ideology celebrates entrepreneurial individualism, and Americans have tended to see communist ideology clashing with these ideals. In the late nineteenth century, most Americans lumped communist politics together with other radical movements of the day: anarchism, socialism, populism, etc.

But the intense aversion to communism that we are familiar with today took form in the twentieth century with the Bolshevik Revolution in Russia. The Bolsheviks pledged to unite the workers of the world and end capitalism. Prominent Americans like Herbert Hoover and Woodrow Wilson interpreted Bolshevism, or Marxist-Leninism, as an ideological challenged to the American Way, which advocated liberal capitalism, democracy, and individual freedoms. As President, Wilson even sent US troops to intervene in the Russia Civil War in an attempt to prevent Lenin and the Bolsheviks from consolidating power. These fears of communism after the rise of the Bolsheviks also manifested inside the United States with the Palmer Raids of 1919, one of the largest civil liberties violations in US history, in which the precursor to the FBI arrested suspected communist activists and radical immigrants across the nation.

These fears died down during the 1920s as Lenin launched his New Economic Policy and American capitalists invested in the Soviet Union. The Great Depression of the 1930s also led to a revival of American communism in the labor movement, though it never became mainstream as most Americans still saw communist ideology as clashing with American ideals.

The point is that this ideological aversion was always there. After World War II, however, this ideological aversion joined with geopolitical realities and threats, cementing American opposition to communism. Americans saw the Soviet Union's domination of Eastern Europe (such as Stalin's refusal to hold free elections as called for in the Yalta Accords) and the conflicts over divided Germany as the next threat to world peace. In February 1946, Stalin gave a speech in which he said that conflict between capitalist nations and communist nations was inevitable. Since the 1920s, the Soviet Union talked about exporting communist revolution abroad. But Americans didn't think much of it at the time, it was a weak nation. Now, though, the Soviet Union was a superpower and it could back up its words with force. The result was the Cold War and a Second Red Scare, like the one after World War I, in the United States. Hollywood movies of the day like The Red Menace and I was a Communist for the F.B.I. really reflect these fears.

This is all just a brief overview to show how American disdain of communism is ideological but also tied to the origins of the Cold War. Americans disliked Communism long before Stalin, but Stalin's actions after World War II, heightened American fears further consolidating American opposition to communism, in general, and the Soviet Union, in particular.

The following books over a strong overview of all of these aspects that I mentioned:

Melvyn Leffler's The Specter of Communism (very short but good summary of all of this material), Preponderance of Power (much more in depth analysis and look at the Truman Administration's response to Stalin);

Odd Arne Westad's The Global Cold War (early chapters over a nice overview of the ideological dimensions);

Campbell Craig and Fredrik Logevall's America's Cold War (follows the Cold War and U.S. domestic politics from 1917-1991).

I'd just like to point out that many Americans (such as myself) are in fact communists, and America has several communist parties that try to be active. Socialist Alternative is a growing party for example, and had a member elected to the Seattle city council (Kashama Sawant), where she fought for, and helped obtain the $15 minimum wage. For clarification, they are in fact an anti-capitalist party with communist goals (I specify because many Americans think that the word socialism means a government with a strong welfare system rather than a government which intends to replace capitalism with communism).

So not all Americans dislike communism, and if you are interested, there is actually a long history of communist thought in the US.

I personally woudl argue that the disdain is mostly accounted by the first red scare. The USA in the end of the 19th century and early 21th century had a very large proletariat, that was drawn to radical left wing ideologies. Interestingly enough, Anarchism was very strong in the USA. You have the IWF and other trade unions. Also the proletariat was much less organized in single parties, like for example the SPD in Germany.

This is partly responsible why there was such enormous violence at demonstrations and strikes in the USA. There weren't parties that could have been drawn into Parlamentarism (like in Europe) and therefore made less radical. You have a very large history of politically motivated violence in the USA.

Once the Bolsheviks won the revolution, US middle class got very frightened. The Sedition act was released and public fearmongering and government opression started to happen. Basically, the labour organisations dominant at the time were destroyed and never recovered. It was at this point that radical left wing ideology became somewhat outside the political spectrum of the USA. If you're an anarchist, your are one of them, not one of us. The thought became absolutely delegitimized. You actually also see a large drop off in feminist literature and activity in the interwar period, because those were largely built into other left-wing movements.

After the Second World War you have the second red scare with McCarthy, that destroyed a lot of left wing intellectualism as well as the Communist party. But I'd argue that Socialism as a real acceptable thought was already pushed out.

Left Wing thought had a ressurgence in the 70ies with the Civil RIghts movement, where it became a more widespread ideology among Black Activists (Black Panthers!) and in student circles, but still could never reach back to its working class roots.