What is Iran’s center of resistance?

.AMERICA SAYS THAT its soldiers in Syria and also Iraq have been attacked at least 55 times considering that Hamas’s assault on Israel on Oct 7th. Pointing the finger at Iran and its stand-ins throughout the Middle East, it has been countering: on Nov 12th United States launched its 3rd set of air raid in far eastern Syria considering that late Oct. Iran’s substitutes possess until now stopped short of launching assaults that could drag United States into major war.

Yet their firepower postures a very clear threat to United States and also its own allies. What is this self-proclaimed axis of protection, and how strong is it?