According to virtually everyone, including Democrats and Europe, Iran was a nuclear threat pre-JCPOA. Trump tore up the JCPOA and Democrats and Europe went ballistic because that agreement was so effective that it was squashing their ability to enrich uranium to weapons grade.(False) Once the agreement was terminated, Iran was going to become a threat again all thanks to Trump. Trump then attacks because Iran stated that they had stockpiles of 60% enriched uranium, thus proving their original point, but all of a sudden they aren't a threat again, despite JCPOA being terminated, meaning JCPOA didn't do squat.
As confusing as this all is, it is actually pretty easy to decipher. Whatever Trump does, they are against it, no matter how illogical that opposition may be.
The true reality is that JCPOA was a disaster. It gave Iran billions of dollars to fund their proxy terrorists(Oct. 7th) and the inspections weren't nearly thorough enough. Iran was laughing all the way to the bank. Trump tore up the JCPOA and it comes out that there were undisclosed enrichment facilities that were not being inspected and viola, they have enough 60% uranium to make up to 9 nuclear warheads. They were a threat both before JCPOA and after JCPOA. The only way to remove the threat is via brute force, not baking them cookies in hopes that they will play nice.