All imperialism is bad. A person can be against Russian imperialism, American imperialism and NATO. NATO’s original mission was a check on the socialism of the Soviet Union. Source.
Today,
Instead of being for collective self-defense, NATO is a means for several of the most powerful states in the world—including the US, Canada, the UK, France, and Germany—to maintain global control of people and resources to serve western capitalist interests. Source
Simply, as a socialist, you can’t be anti-capitalist and pro-NATO. Vaush is not a socialist. He’s a social democrat at best, which is fine. But don’t lie to your audience and misrepresent yourself.