Let's see, there was an implementation day last month where the UN certified that Iran has fulfilled its obligations under that 7/15 agreement to dismantle its nuclear program by giving up their enriched uranium (25K lbs or 98% of their stockpile), 2/3 of their centrifuges and their heavy water reactor. They can't make a bomb now. That's how they've been disarmed. 5 other world powers were in this agreement with Iran btw, not just the US.
Iran also released 5 US prisoners. Without going to war. Which proves that diplomacy and economic sanctions work in lieu of invading yet another Muslim country which republicans obviously hate. But yeah, let's go back to how it was when we didn't engage with our enemies like Iran and didn't talk to them for years like W.Bush did and let their nuclear progam explode and their centrifuges increase by tens of thousands. That worked great.