Correction: An earlier version of this column said that “Iran dialed back its nuclear-reprocessing efforts as part of the negotiations.” It should have referred instead to Iran’s nuclear-enrichment efforts. The following version has been updated.

Opinion writer

The worst moment of Israeli Prime Minister Benjamin Netanyahu’s speech to Congress, at least for me, came when he used Elie Wiesel, a great moral hero, as a Hollywood-style prop. Presidents giving State of the Union addresses have the right to tug at our heartstrings by saluting honored guests in the gallery. Foreign leaders taking advantage of partisan invitations do not.

The best moments came when Netanyahu showed a more nuanced and realistic view of the Iran nuclear negotiations than his generally bombastic tone would suggest. But you had to listen carefully.

After imploring Congress to reject the deal with Iran that seems to be brewing, calling the Iranian nuclear program an “existential” threat to Israel, Netanyahu allowed that there is a potential agreement his nation “could live” with. Among other things, he said, Iran should not have “such a short breakout time.”

The term refers to how long experts believe it would take Iran, given the nuclear equipment and materials in its possession, to complete an all-out dash to build a nuclear bomb. It should be noted, for the record, that the Iranian government firmly denies any intention to build nuclear weapons, now or in the future.

The breakout time reportedly under discussion is one year. The Israeli government believes this is insufficient for the international community to react effectively with new sanctions, an Israeli official told me, which would leave a military strike as the only option to prevent a bomb. Netanyahu would therefore like to see a considerably longer breakout time.

But here’s the thing: The fact that Netanyahu raised the issue implies the assumption that Iran will be left with some nuclear infrastructure, including the ability to enrich uranium. Otherwise, the question of breakout time would be moot.

Israel’s stated position has been that Iran should have no ability whatsoever to produce fissile material. Netanyahu effectively acknowledged that the “zero option” — an Iran stripped of all nuclear capability — is a fantasy. An agreement is likely to leave Iran with some number of enrichment centrifuges, and Israel “could live” with that.

At another point in the speech, Netanyahu said negotiators should demand that Iran stop committing aggression against its neighbors, supporting terrorism around the world and “threatening to annihilate” the state of Israel. Then he added that Iran should do these things if not before a deal is signed, then at least before a deal expires. This was another attempt to engage with reality.

The agreement being discussed would reportedly last at least 10 years, after which it would expire. At that point, Iran’s nuclear program would be bound only by the nation’s obligations under the Nuclear Non-Proliferation Treaty, which prohibits a weapons program but allows enrichment on a scale that Israel and other countries in the region consider dangerous.

Supporters of an agreement argue that it would be a real accomplishment to confine Iran in a nuclear straitjacket for at least a decade, especially given the alternatives — a sanctions regime that may or may not hold, the potential for covert nuclear development, the possibility of war. Moreover, as the government in Tehran saw the benefits of reengagement with the international system, it would have every incentive to become less threatening.

Netanyahu was saying, essentially, that rather than hope for a kinder, gentler Iran, negotiators should insist on it by requiring specific changes in behavior by the time an agreement expires. He made a point of clarifying that he was not expecting Iran to take these steps immediately, but over the course of time.

Imagine, for a moment, what would happen if the negotiations were to fail. Clearly, from the thunderous reaction to Netanyahu’s speech, Congress would be ready to impose tough new sanctions. But what about the other powers involved in the negotiations? Does anyone expect Russia and China to help bring the Iranian economy to its knees? Would even Germany, France and Britain be enthusiastic about a new sanctions regime, absent some new provocation from Iran?

Remember that Iran dialed back its nuclear-enrichment efforts as part of the negotiations, and as a result is further from being able to make a bomb than it was a year ago. A military attack by the United States or Israel would be difficult to justify unless Iran cranked the program back up.

Netanyahu was full of bluster — perhaps mostly for the voters back home, who go to the polls later this month — but there were nuggets of realism. I hope Congress actually listened.

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