When will realize that we aren't very good at fighting guerrilla wars?

We continue to think that Patton's Third Army is still rolling across Europe. We tried to bomb an agrarian country (Vietnam) into submission and failed. We failed at the same mission in Afghanistan. All the planes and bombs in the world can't subdue brave fighters on their home turf. There are no ball bearing factories to bomb in Yemen. Add an addled, feckless commander in chief and we're headed for another humiliation.