In my opinion, We’ve spent $4 trillion trying to topple various people that, frankly, if they were there and if we could have spent that $4 trillion in the United States to fix our roads, our bridges, and all of the other problems — our airports and all the other problems we have — we would have been a lot better off, I can tell you that right now.

We have done a tremendous disservice not only to the Middle East — we’ve done a tremendous disservice to humanity. The people that have been killed, the people that have been wiped away — and for what? It’s not like we had victory. It’s a mess. The Middle East is totally destabilized, a total and complete mess. I wish we had the 4 trillion dollars or 5 trillion dollars. I wish it were spent right here in the United States on schools, hospitals, roads, airports, and everything else that are all falling apart!

Donald Trump

CNN Republican debate in Las Vegas, December 16, 2015