Doesn’t matter how advanced your weapons are if you have not enough money to use enough of them and not enough soldiers that would like to come and kill other people that can also fight them back. So, while the USA has high defending potential, it has not enough politically approved resources for a long occupational war. Only short quick operations are now possible, since the USA citizens are against the war and greatly affect the leadership authority of current government, so that it cannot waste money to launch a full scale war as it was before. Especially, because of this doesn’t pleases oligarchs which have great leverage in this situation.