Earlier quoted context omitted.
The expansion of NATO deep into former Warsaw Pact countries.
>The western powers have been doing most of the invading lately. That's what you're replying to. Several former Warsaw Pact countries joined NATO. The West didn't invade them.
Every empire needs aligned, friendly, or at least, neutral buffer states on their borders - and will violently defend incursions into their buffer zones. Observe the shitshow over Cuba - sixty years of sanctions, terrorism, assassination attempts, an invasion, and a nuclear crisis later, the United States still hasn't forgiven it.
The United States was ready to bathe the entire world in nuclear fire - because a neighbouring country entered into a military alliance with the USSR. Let that sink in... And then consider what expanding NATO into Eastern Europe, US support of Georgia, regime change in Syria looks like from the Russian point of view.