We retreat, reassess and plan the next attack.
In the mean time we fight to win. We have a warrior taking hits for us and we need to pick up our share of the battle.
But the reality is the battle goes back to state and local as Our Founding Fathers designed. If you lose state and local, you are lost. “A well regulated militia being necessary.............” It is time to group up NOW.
In our lifetimes we have witnessed the demise of a major world power. It is an interesting study. It is possible that may happen to us.
To further answer your question, what does history teach us? This is not the first time things have happened.
If we meet our demise as a world power, we will have to count on the kindness of the CCP.....