The American army forces are for sure the most powerful single military force in the world.

I don't think that there can be much objective argumentation against that.

Having such a powerful army, does not mean its allmighty however. Its incredible hard or impossible to beat good organized and trained guerilla forces with a stable supply source with any army of the world.

PS:
I am from Europe, I feel no need in exaggerating the power of the US armed forces.