Russia is but a shadow of what it once was, they would be no competition for America let alone all of NATO, Putin knows this and this would be why he constantly throws down the "nuke" card.
I'm not sure about your words.
When the US was "expanding" took by force lands from Mexico and from Hawaii, but when it was the turn of Alaska, instead of force it was a business deal.
The same "respect" towards Russia in the past by the US still is present today.
The US learned a hard lesson with Vietnam. In this war, the enemy received the same arms to equalize the US military power. This war was a "one to one" fight, where both opponents had the same strength to fight and overcome the adversary. The Soviet Union supplied the required armament for the Vietnamese.
Vietnam was lost not because the US was incapable to win, but because the Vietnamese was defending their land and they had strategic support to respond the attacks of the US army. It was a war not only against Vietnamese soldiers but also against civilians.
After this lesson, the US has not participated in any other great war "without a coalition". This is to say, to win against Iraq, the US had no other choice but to use bases in Saudi Arabia and other countries. The US managed to stop any strategic help from Russia which should allow Saddam Hussein to respond as the Vietnamese did it in the 70's.
No doubt that without this "coalition" and fighting against Iraq having the same armament -including war airplanes, helicopters, etc.- to respond the US attacks , perhaps it should become another "Vietnam" for the US army.
Just think about it. The US fighting without the help of the neighbor nations against Iraq should be a complete disaster and the use of "Orange Product" weapons should be the only solution to end a war with Iraq.
If this scenario is possible with a small nation like Iraq, I think that attacking Russia by the US should be suicidal. The US should need of a coalition to win a war against Russia. Military bases in neighbor countries must be needed for supplies, deployment of troops, and more.
Just look what happened recently, Russia took Crimea in front of the whole world. Where were the US, France, UK, China, Italy, and more, after this taking of land by Russia?
Why not attacking Russia to "free" Crimea like it happened with Kuwait?
I think that you can't tell that Russia is not what it was in the past. On the contrary, Russia proved that still is strong and that it can take lands when they decided to do so.
The only respond for their land taking was "economic sanctions", which might be working in one way, but eventually will affect the US and the worldwide economy at the end.
And yes, Russia might use the nuke card if it is invaded, and this is a major reason for not to mess with this nation. The US used it in the past, why other nations can't use it when they think is OK to do so?
And this is the ideology: for us, we are the good guys and they are the bad guys. For Russians, they are the good guys and we are the bad guys.
Who is good and who is bad depends on your place of birth. That's all.