I agree with much of what u/epictortoise said, but don't think it's the sole reason for targeting left-wing governments.

Left-wing governments tend to nationalise assets and resources owned by foreign corporations - believing that the profits from a mine, agricultural company, or similar should stay in the country (and in theory, the profits be redistributed to the people, although whether that actually happens depends on corruption levels). Since the US government is and has historically been heavily pro-corporate, this represents a loss to them.

As a generalisation, right-wing governments are more pro-corporate than left-wing governments.

In Central America, the US intervened because local governments were a threat to US corporations such as the Haitian American Sugar Company and United Fruit Company (hence the term 'banana republic').

e.g.
"In 2007, Chavez’s government took a majority stake in four oil projects in the vast Orinoco heavy crude belt worth an estimated $30 billion in total.

Exxon Mobil Corp and ConocoPhillips quit the country as a result and filed arbitration claims. Late last year, an arbitration panel ordered Venezuela to pay Exxon $908 million, though a larger case is still ongoing."

" In 2009, Chavez nationalized a rice mill operated by a local unit of U.S. food giant Cargill Inc."

" In 2007, the nation’s largest telecommunications company CANTV was nationalized after the government bought out the U.S.-based Verizon Communications Inc’s 28.5 percent stake for $572 million. Analysts said Verizon received fair compensations for its assets."
https://www.reuters.com/article/us-venezuela-election-nationalizations/factbox-venezuelas-nationalizations-under-chavez-idUSBRE89701X20121008

Under ordinary definitions of "left wing" this is not accurate. The Axis powers (Japan, Nazi Germany and Fascist Italy) are not usually considered left wing. Most people would also not classify the Taliban as left wing. There are other less well known examples such as Operation Uphold Democracy (Haiti 1994-1995) or the Invasion of Panama (1989) where the US targeted regimes that weren't left wing.

There are a substantial number of cases where the United States targeted left-wing governments during the Cold War, and the reason for this is fairly simple. The targets tended to be aligned with the Soviet Union and hostile to the United States. The US was particularly concerned by Soviet aligned countries in the Western Hemisphere because of the security risks this would pose in the case of a war between the two powers (think Cuban missile crisis). Prominent examples of US involvement against Soviet aligned left-wing governments in the Americas include against the Sandinistas (Nicaragua) and the long opposition to Castro's rule in Cuba.