Tankie is a general term for someone who thinks there is a clear justification to use force or the threat of force to impose a socialist system on a state.

By this “definition” every non-reformist socialist is a “tankie”.

Funny how you claimed to be a socialist previously, but now you imply that basically all socialists are bad.

The term originates with people who supported the USSR “Sending in the tanks” to annex other countries and crush dissent from people in their sphere.

Firstly, which countries did the USSR annex when the “tankie” pejorative was coined? Any annexations after that?
Secondly, the “dissent” in question were NATO-backed nazis. Please tell us why you think that forcing capitalism on a country is good in your eyes, and should not be opposed.

What actions do you even disagree with here?

They’re terrified of them, because in their heads the most terrifying thing in the world is a leftist that is willing to fight back, and they don’t recognize anything that doesn’t kill someone as “fighting.”

This is extremely funny, considering that your position seems to be “the rest of the world should be subjugated by NATO, and everybody else is bad to take forceful action against that”, which is very much not “leftist”.