The US only became a “world imperialist” country after World War 2 with the Cold War. We were “imperialist” before but it was generally just a “local imperialism” only in the Western Hemisphere, similar to that of Israel in the Middle East, India on the subcontinent, or even the Japanese in Asia.
“World imperialism as a thing is a rather new phenomenon that mostly took place after WW2, though the British did try their best for a while, with “the sun never sets” and all that. Nevertheless, if WW2 did anything, it knocked the British off their world controlling perch, where they were promptly replaced by the US, this change because of the devastation the war had wreaked on the UK.
Before, the Spaniards had made their world controlling attempt that was smashed with the defeat of the Armada. Rome tried for control of at least the known world anyway, a fairly benign tax-farming sort of colonialism that faded away rather than being smashed.
We didn’t care much about the rest of the world prior to World War 2, though we got involved in the Russian Civil War.
In general, “Bolshevism” was a problem for Europeans and not the US, and we were not really involved with the European continent until after WW2. In fact, many Americans, especially Republicans, had become isolationists at this time. The general attitude was that Europe’s problems were their own and not ours, and we needed to butt out of the external affairs of others and mind our own business and let them settle their problems or fight it out among themselves, just leave us out of it, thank you.
This of course had a long history in the US dating all the way back to the Revolution and George Washington’s warnings about avoiding foreign treaties and entanglements. On the other hand, it was an alliance or entanglement with French that allowed the revolutionaries to win in the first place so one wonders to what extent he really believed this or if this was more of an ideal that an actually existing or even preferred thing.
On the other hand, Communism, socialism, and the slightest bit of liberalism was a problem over here in which the Monroe Doctrine was invoked on a false basis in Haiti, Cuba, Mexico, the Dominican Republic, Panama, and Nicaragua. It was not seen as Bolshevism or Soviet-inspired until after the Cold War, beginning with Guatemala in 1954.
There was an actual Communist uprising in El Salvador in 1932, and the Mexican Revolution was definitely a Left revolution, not to mention Sandinism in Nicaragua (though this was also very nationalist and anti-Yankee), but the US did not see these as “Bolshevist”-inspired, and indeed, the Mexican Revolution took place before Bolshevism was a thing.
The term Bolshevism, by the way, at the time and to this day still obscenely used by anti-Communist kooks, always had strong anti-Semitic overtones, and indeed, it was the invocation this beast that was in large part a rationale for the mass murder of Jews known as the Holocaust. So I’d avoid using that word if I were you unless you want to harken back to one of the worst things we humans have ever done in terms of degree anyway.