No nuclear weapon has been deployed in war since the U.S. dropped atomic bombs on Hiroshima and Nagasaki in Japan in 1945, and any use of such weapons against an Iranian facility would be extremely controversial in the U.S. and worldwide.

Negotiating with Tehran is time-consuming and difficult under the best of circumstances. And it remains unclear whether President Trump’s 14-day clock is more than a way to buy time for military preparations.