When the presidential candidates for the first time open up foreign policy for debate, one of the questions we want to see Governor Romney put to President Obama is in respect of Jerusalem. We were reminded of this by an op-ed piece by Nathan Lewin in the Forward. If Mr. Obama really believes, as the Democratic convention declared he believes, that Jerusalem is the capital of Israel, writes Mr. Lewin, “why is he contesting in court a modest recognition in American passports — validated in a law enacted by Congress — simply stating that Jerusalem is in Israel?”

Mr. Lewin is referring to the case known as Zivitofsky v. Clinton, now before the United States Court of Appeals for the District of Columbia Circuit. This is the case in which an American child, Binyamin Zivotofsky, who was born at Jerusalem, is seeking to have a passport granted to him stating that he was born in Israel. A law passed by Congress in 2002, shortly before he was born, requires the state department to issue him such a passport on his request. Secretary Clinton and Mr. Obama, however, are refusing to bow to that law.

They are not the only ones. President George W. Bush and his state secretaries also refused to bow to the law, on the grounds that it infringes on the presidency’s powers and prerogatives. At first the courts tried to dodge the issue, on the grounds that it was a political question that was non-justiciable. The Supreme Court ruled that the political question had been dealt with politically — that’s what the Congress did in passing the law. The job of the courts, it said in no uncertain terms, is to decide whether Congress acted within its constitutional powers.

It may be — the Sun is just speculating here — that Mr. Obama and Mrs. Clinton fear that if they issue Master Zivotofsky a passport asserting that he was born in Israel, it will start a war. Justices Sotomayor and Scalia pressed that question hypothetically during the hearing before the Supreme Court. The answer that seems so clear is that if it is war that the president fears, then the question is up not to the president but rests precisely with the Congress. It is to Congress, after all, that the Constitution grants the power to declare war.

A presidential debate is not a federal court case. Tant mieux, as the French say. So much the better. What a terrific venue an open debate is for pressing Mr. Obama on this question. It’s not that the passport of Master Zivotofsky is the be all and end all of foreign policy. But it is a hugely important question for an American individual. Not untypically for great court cases, it is almost always in an actual case or controversy involving a real person’s real-life problems that our greatest constitution questions arise. The question for Mr. Obama is why, if he believes what he says he believes, is he not standing up for his beliefs.