Senator Schumer is going through quite a drama over how to vote on the Iran deal. Publicly, New York’s senior senator is keeping his cards close to his chest and complaining about what a difficult decision it is.

My guess is that Mr. Schumer is going to get behind the president, rebuff Israel’s objections and, in the end, vote for appeasement. That’s the implication of a little-noticed YouTube video on which he was last month captured talking with a delegation of Orthodox Jews in Washington.

The video has been given little coverage, even as Mr. Schumer emerges as a pivotal figure in the debate in the Senate. The meeting was with a delegation of one of the most distinguished Jewish groups, the Orthodox Union. It was apparently filmed by a news site called Jewish Insider and was uploaded onto YouTube in June.

Mr. Schumer was aware of that possibility, because he started out by saying he’d “wanted to talk a lot of tachlis about Iran” — meaning, roughly, get down to business. But, he said, “I’m not going to do this because you’re recording it.”

Then he proceeded to talk tachlis anyhow, characterizing the question as “which is better — no agreement or an agreement that is not close to the ideal.” It would, though, be inaccurate to suggest that Mr. Schumer simply endorsed what the administration is doing.

Mr. Schumer was nuanced and thoughtful. He gets that an Iranian bomb would be an existential threat to Israel. But he mocked those who advocate a military strike against Iran’s bomb-making facilities, calling it “the next-worst solution.”

“Tens of thousands of Israelis would die,” he warned, expressing fear that an attack would trigger terrorist strikes against America and prompt Hezbollah to launch 10,000 rockets against Israel. Backers of a military solution, he suggested, “are not looking at the facts.”

“As a Jewish leader in America,” Mr. Schumer said, “I have to look at the facts.” Bizarrely, he vowed: “I will not be pushed around on this issue.” Did he mean pushed around by the Iranians, by the administration or by Israel?

“An agreement that everyone likes” is what Mr. Schumer called the best — but extremely unlikely—solution. Hence the question of which is better — no agreement or an agreement that is not close to ideal.

What was most astonishing about the Schumer remarks was when he touched on the issue of dual loyalty. He imagined a hypothetical agreement that had a 95 percent chance of ensuring that Iran would not get an A-bomb.

“If you are president of the United States, president of one of the European countries or an American, an average American, you say that’s pretty good to me,” he said. But since a nuclear Iran would be an existential threat to Israel, he suggested, there’s another perspective.

“If you’re prime minister of Israel or an Israeli citizen or for that matter an American Jew or at least some American Jews,” he said, “you say I can’t live with a 5 percent chance that Israel will be annihilated.” So “there is a basic difference in viewpoint.”

Mr. Schumer also spoke of how the “American Jewish community ignored the threat of Hitler,” suggesting some kept quiet out of fear of being accused of dual loyalty. Then, toward the end of his remarks, he asked that the door be closed.

“This is the tachlis part,” the senator said. He spoke of how the failure to reach an agreement would leave sanctions in place but only if everyone else stays in. “It so bothers me to have the Jewish fate in European hands,” Mr. Schumer said.

“We’ve been through this before, we Jewish people,” Mr. Schumer said. He then spoke of what a difficult decision he was facing. Noting that he’d been an elected official for 41 years, he said he would not let political pressure interfere.

Yet maybe Mr. Schumer will remember Mordechai’s injunction to Esther: “If you remain silent at this time, relief and rescue will arise for the Jews from elsewhere, and you and your father’s household will perish.”

A version of this column was originally published in the New York Post.