It's horrible to waste soldiers for nothing, which is what's been going on over there for quite some time. The problem is, it is a total sacrifice - people losing their lives for nothing.
If it really is 'waste' that people are worried about, why not that?
You mean Saddam Hussein (Iraq) and the Taliban (Afghanistan)?
But yeah, I definitely think we should have acted much more forcefully to end the wars much more quickly and with far fewer casualties on both sides.
I think we probably could do this without resorting to nukes, but applying the same "kind" of intense pressure. Hiroshima/Nagasaki were huge successes compared to a minimum decade-long ground invasion and occupation of Japan resulting in possibly millions of deaths.