New Delhi, June 19 -- The interim deal between the United States and Iran is supposed to usher in a two-month period that would address the most divisive issue between the longtime adversaries - Tehran's nuclear program.

Preventing Iran from attaining a nuclear bomb is a key reason that President Donald Trump said he launched the war alongside Israel in February, but the tentative agreement he has trumpeted leaves little runway to negotiate the long-running sticking point. The previous nuclear pact between Iran and world powers, from which Trump pulled the U.S. in his first term, took many months to negotiate.

Under terms of the initial deal, Iran would immediately take steps to reopen the Strait of Hormuz to global oil shipments and wo...