The US is running out of bombs, we have no bombs left to give. 
There's the nuclear option

Iran only understands bombs.
If you mean instead accepting total capitulation and accepting their partner breaking all agreements then yes, America responding by killing them all would be the other option. I think it's really rich for some Americans to insinuate that since America signed a bad deal then America should resort to bombs. How about honoring commitments? It's also pathetic to insinuate Iran is unreasonable and can't be trusted bearing in mind everything that happened here. It's also interesting that just the other day Trump said the Iranians are very smart and great negotiators, the thing Trump sees himself as. He knows the Iranians aren't irrational and suicidal as many Americans see them as.
Trump is getting absolutely roasted by both sides of the isle so now he's immediately back to making murderous and genocidal threats to get back some of his lost credibilty as a tough man. The deal forbids threats. Trump even threatened Aragchi and Ghalibaf by saying they might not even get back to their country. That's ridiculous and not honorable but some peoplr don't care about such silly things. I fear if the war resumes because Trump fears looking weak (when in fact he's corageous) the nuclear option becomes more likely. Obviously the conventional means didn't work and the types of missiles used so far, like the Tomahawk, have almost ran out.
One thing that might force Trump to eat dirt for the time being is that the oil reserves have run out. If hostilities resume now the "bedlam" he talked about will become real. If the oil flows Iran is doing the US a favor. It's in Iran's favor too though, not denying that, but they have lots of hardliners who are opposed to this but the government is attempting anyway.