Iran will no longer be a threat to the Free World

Why would Iran no longer be a threat to the Free World?

That would be true if we could force a change in the governing regime from an enemy of the Free World to one that was supportive of and friendly to the Free World. But that's incredibly unlikely to happen. It's not even a formal objective of our mission, at least according to the Administration (other than Trump) - we're just there to degrade Iran's current military capabilities, not to decide what the future government of Iran will look like.

So it's entirely possible, and indeed fairly likely, that the government of Iran in five years will be exceptionally similar to the government of Iran today. And therefore again pose a threat to the Free World. Oh, sure - they won't necessarily have the same proxies in five years (any more than Iran had the same proxies shortly before the war than they did five years ago, after Israel had inflicted so much damage on Hamas and Hezbollah). But they'll be able to build up their armed forces, their missile programs, and (perhaps) their nuclear program again.

Sadly, by doing this we've kind of confirmed what the Khameini regime has been pitching to the Iranian people all these years. If you're not a nuclear power, you're never safe - and the ostensible "global rules-based order" will not protect you from the U.S. just coming in and blowing up your country. We might be able to physically keep them from making much movement towards a nuke going forward (as we have for the last decades), but it doesn't seem likely that whatever Iranian government comes out the other end of this will have changed their position on whether nukes are an important policy goal.

If you don't change the regime, you don't change the threat all that much - except during the actual time that you're dropping the bombs and the short-term thereafter. Right now, it looks like we will have used up several tens of billions of dollars of important military hardware - especially our missile interceptor inventory - and end up without much of a long-term change in the country.