Guess who turns out to be at the center of the great Jerusalem Passport case that is going to be appealed for a second time to the Supreme Court. This is the case that determines whether the president must obey a law passed almost unanimously by Congress, granting to Americans born in Jerusalem the right to have a passport and other official documents listing their place of birth as Israel.

It turns out that the measure was introduced in the Congress by none other than Anthony Weiner. This was back in 2001, when the current candidate for mayor of New York was a member of Congress from Brooklyn. It was before he was caught up in the sex scandal that cost him his seat in Congress and appears likely to cost him the mayoralty. It is a reminder of the cost of — the irresponsibility of — Mr. Weiner’s licentiousness.

The law he introduced in Congress was an attempt to confront the hostility to Israel and the Jewish people that has become institutionalized in the State Department since before the creation of the Jewish state. It should have been an easy call for the state department to issue birth documents stating that if Jerusalem was where an American was born, the country in which he was born was Israel. Particularly after the Jerusalem Embassy Act was passed, declaring it the policy of the United States that Jerusalem is the capital of the Jewish state.

Mr. Weiner didn’t have to pick up this issue. He would have been handily re-elected if he had not. But he did because he and his constituents believe profoundly in the issue. So the law to require the state department to honor the request of an American born in Jerusalem to have the proper birth documents, this was a creative and admirable demarche. It bespeaks the kind of creativity and gumption that are the good side of Anthony Weiner.

We were reminded of the background to Mr. Weiner’s involvement in the issue by Paul Kujawsky, the constitutional lawyer who filed for Mr. Weiner an amicus brief in the case known as Zivotofsky v. Secretary of State, in which an infant, Menachem Binyamin Zivotofsky, has been demanding his rights under the law that Mr. Weiner initiated. The brief is but one of the filings that has been made in the case, which hasn’t gone well for Master Zivotofsky but which isn’t over.

Mr. Weiner may survive politically after the disclosure that the behavior that scandalized the Congress continued after he left office. But our guess is that his behavior has cost him his political career. Let it be a reminder that if one is involved in a great cause, one has to behave in a way that protects and honors that cause. It marks the difference between a leader for the long haul and one who is destined to become a footnote. Which is what Mr. Weiner is likely to be, even if Master Zivotofsky wins his birthright under the law Mr. Weiner set in motion.