Last week, Senator Rand Paul set off a furious debate by putting forward a bill that would cut off aid to the Palestinian Authority because of the decision by its leaders to conclude a unity pact with the Islamist terrorists of Hamas. But rather than reap the applause of Israel’s backers, his bill was opposed by AIPAC. Paul’s latest attempt to curry favor with Jews and other members of the pro-Israel community was excoriated by the Washington Post’s Jennifer Rubin and wound up failing in the Senate.

I thought Paul was wrong to blast AIPAC as betraying its mandate. I also think his isolationism and steadfast opposition to vital military aid to Israel calls into question his bona fides as the author of legislation he called the “Stand With Israel Act of 2014.” But I also disagreed with those who thought the libertarian was wrong to call into question the continued flow of U.S. taxpayer dollars to the PA. The basic flaw in America’s efforts to bolster the peace process from Bill Clinton’s day to the Obama era has been an unwillingness to make the Palestinians accountable for their actions.

But yesterday, Senators Marco Rubio and Mark Kirk provided a timely reminder as to why Paul’s bill was really unnecessary: an aid cutoff because of the Hamas alliance is already mandated by U.S. law.

As Rubio and Kirk wrote in a joint letter to Secretary of State John Kerry:

The Palestinian Anti-Terrorism Act of 2006 sets detailed requirements for the continuation of U.S. assistance should Hamas be brought into the Palestinian Authority government. The law is very clear. If Hamas comes to have a role in governance, there must be public acknowledgment of the Jewish state of Israel’s right to exist as well as acceptance of all previous agreements the Palestinians have made with Israel, the United States, and the international community. The law also requires that demonstrable progress be made toward dismantling of Hamas’ terrorist infrastructure and purging of individuals with ties to terrorism. Moreover, Hamas would need to halt its anti-American and anti-Israel incitement. The bar is high because the stakes are high and we must make sure to stand firmly by what we have said. Failing to do so will diminish the credibility of the United States.

Rubio and Kirk are right. No new legislation is needed to make the Palestinians accountable. All that is needed is for the administration to start enforcing the law.

That it won’t do so is pretty much a given. The reason put forward by some in the pro-Israel community for keeping the flow of Uncle Sam’s cash to the PA is a reasonable one. They claim that Israel needs the PA to continue to exist. A collapse caused by the cutoff of Western funds would cause huge problems for the Israelis who always need a Palestinian interlocutor. Israel has no desire to directly interfere in the lives of West Bank Palestinians, most of whom are governed by the corrupt and incompetent PA. It also relies on security cooperation with PA forces to help keep a lid on terrorism, though it can be argued that the PA and its fearful leadership benefits even more from the relationship because the Israelis ensure that Hamas and/or Islamic Jihad can’t topple them as they did the Fatah government of Gaza in 2006.

But as Rubio and Kirk noted in their letter, the deal between Hamas and Fatah explicitly states not only that Hamas won’t disarm or cease support for terror and recognize Israel. Hamas believes the agreement forbids further security cooperation between the PA and Israel.

That pronouncement illustrates Prime Minister Netanyahu’s point about Abbas having to choose between peace with Israel and peace with Hamas. In his desire to flee Kerry’s peace talks rather than be maneuvered into signing a peace agreement he can’t enforce, Abbas has chosen the latter. And U.S. law dictates that consequences must follow.

The key point here isn’t so much about the money, though U.S. aid plays a vital role in keeping the PA kleptocracy afloat. Rather it is that for more than 20 years U.S. governments have been whitewashing and excusing Palestinian actions and defending those decisions by saying that holding the PA accountable is bad for peace, security, and stability. Just as the failure of Kerry’s initiative was due in no small measure to the refusal of the administration to tell the truth about Abbas—who was wrongly praised as a man of peace while Netanyahu was falsely blasted as intransigent—that led the Palestinian to believe that he could stall and then walk out of talks with impunity.

Until the U.S. government starts enforcing those consequences, their behavior will never change. Paul’s bill may have been a piece of unnecessary grandstanding and friends of Israel are right to be wary of an isolationist whose rise bodes ill both for the future of American foreign policy and the U.S.-Israel alliance. But the issue he highlighted is real and demands action that unfortunately won’t be forthcoming from Obama or Kerry.