In fact, if you ask the hearts of Americans, Americans also think so. If Mexico had formed a military alliance with Russia, the Americans would have gone to war. This is why Biden said at the beginning that he would not send troops, but that sanctions would be in line with the interests of the United States. The international reality is still power politics. When Russia attacked Ukraine, the United States also bombed Somalia. Who said that the United States violated the sovereignty of Somalia? Because we all know it's out of control.
Big countries and small countries have different ideas, The United States was in the Cuban crisis. Russia is also unlikely to concede in Finland, Ukraine and Belarus, and it also needs a buffer zone. China will not let Vietnam and North Korea loss of the status of a buffer state.
NATO is Europe and the United States in the expansion of their own buffer zone, the buffer zone has been pushed to the opponent's doorstep.