I'm assuming you weren't referring to DHS when you mentioned increasing homeland defenses. DHS is a useless money pit.
As for the military being able to take and hold things, does Somolia ring a bell?...Black Hawk Down? We couldn't even handle that little piece of shit, so don't be so sure about our capabilities. If you were talking about wars with tanks and ships and planes, it's all good, but then you're referring to the types of enemies we worried about during the Cold War. Times have changed, and an insurgent war on their turf ain't so easy a nut to crack.