And? Has that ever deterred the US from engaging in wars against Soviet interests that were seen to be threathening US interests around the world during the Cold War, whether that be done through proxy (e.g. Afghanistan) or being directly involved (e.g. Vietnam)?
Seems like you're the one who needs to relearn history. Cold War isn't as simple and clear-cut as many ought to think/believe.
That's true.
The United States, which became the dominant imperial power, and because the United States, internally one of the most liberal states, conducted the most aggressive foreign policy, while the former Soviet Union, for example, with its totally illiberal (repressive) domestic policies, adopted a comparatively peaceful and cautious foreign policy.
The United States knew it could militarily defeat any other state; therefore, it was aggressive. In contrast, the Soviet Union knew it was doomed to lose a military confrontation with any state of considerable size unless it could defeat it in a few days or weeks.