Explain how it's unreasonable to not want a nuclear Iran.
I think you misunderstood what I said. It is perfectly reasonable to not want Iran to have advanced nuclear technology which allows them to develop nuclear weapons. Wanting and actually achieving this are not the same thing.
Iran and the U.S. have been at odds since the late nineteen century. Including the official large-scale, country-on-country declared war that was the Iran-Iraq War. That conflict lasted for eight years, starting in 1980 and ending in a ceasefire in 1988. Iran's non-compliance spans multiple decades and treaties, including in 2005.
What is not reasonable is believing Trump is capable of reaching an agreement which requires Iran to make an indefinite commitment to never develop nuclear weapons and dismantle its nuclear infrastructure. Keep in mind that since last February Trump has claimed somewhere around forty times that the war and negotiations with Iran are almost over and that a deal is imminent.
I sincerely hope that I am wrong and by some miracle, Trump can make the deal and end the war with Iran.