terrorist groups would lose power. They are currently empowered by our fp. Iran may or may not get a nuke. There incentive would be less if they didn't feel threatened. Either way there is no evidence they would become a "global threat"... Just look at the last time they invaded anther country.
There is an outside chance that we could prevent the destruction of the dollar. There is an outside chance we could get the debt under control. Neither of these are possible with our current FP.
There is literally NO upside to our current FP... unless you are a war profiteer.