Although the controversy surrounding the misleading open letter by 47 Republican U.S. senators to Iran—an attempt to sabotage the Obama administration’s possible agreement with that nation limiting its nuclear program—has broken down along party lines, the senators did violate at least the spirit of the United States Constitution by undertaking this unprecedented act.

The letter addressed to Iran warns the Iranians, distrustful of U.S. motives since President Eisenhower’s overthrow of a democratically elected government in 1953 and reinstatement of a despotic Shah, that if they sign an executive agreement with President Obama, the next president could just rip it up. The deception lies in that while such a reversal is technically possible, it has been seldom used by presidents in the past. Like judicial rulings, precedent does usually hold. In this case, with other nations signing the agreement besides Iran and the United States, the likelihood that any agreement would be reversed is even more remote. In fact, the U.S. Constitution prescribes that the president has the power to make treaties with foreign nations, with the advice and consent of the Senate, as long as two-thirds of Senators present vote to ratify any pact, but does not prescribe what to do if the United States wants to abandon a treaty. So President Obama could make the argument that even if he made a treaty, instead of an executive agreement, the next president could abrogate it too.

The Constitution intended that the Senate give “advice” to the president before deals with foreign countries are reached and that it ratify them after the fact with the two-thirds vote, but gave the president the power to negotiate—that is, make—treaties in the first place. Because the Senate does have the chance to vote down a treaty after the pact is signed, the nation’s founders certainly did not intend for Senators to try to sabotage ongoing negotiations. Senator Rand Paul (R-KY), usually a dove but likely running for president in a hawkish Republican field, rationalized his signing of the letter by saying that he was really sending a message to Obama. The problem is that the letter was not addressed to Obama and thus did not fall under the Senate’s “advice” role.

All that said, the Republican senators’ position is not without some merit. Nothing in the Constitution talks about the president making unratified executive agreements with foreign lands. All arrangements with foreign countries were supposed to be treaties that had to have the aforementioned supermajority approval before they became the law of the land in the United States. That high bar for approval was designed to prevent what is now happening and has been happening since the 1930s—rule by executive fiat. Since that time, only six percent of agreements with foreign nations have been treaties and 94 percent have been executive agreements—found nowhere in the Constitution. Thus, although the Constitution actually provides the Congress more powers in national security than the president, the imperial presidency has not only usurped the Congress’s war-making and budgetary powers, but also its treaty ratifying power.

Obama is not the first president, however, to abuse the Constitution in this way. Presidents of both parties have been guilty of it. In 1945, Franklin D. Roosevelt undertook as an executive agreement the Yalta pact with Winston Churchill and Joseph Stalin constructing the post-World War II world. Richard Nixon ended the Vietnam War in 1973 with an executive agreement. Jimmy Carter used one with Iran to free the hostages in 1981. And recently, Republicans supported George W. Bush’s executive agreement with Iraq on a timetable for the withdrawal of U.S. forces by 2011.

The ham-handed Republicans—in their zealous and misguided attempt to torpedo a nuclear agreement with Iran that they haven’t seen, because negotiations are not yet complete—unwittingly undermined their laudable goal of demanding some role in approving any agreement. Bi-partisan support was building for Republican-driven legislation to force President Obama to bring any agreement before Congress for review (better comporting with the spirit of the Constitution, if not fulfilling the higher bar for treaty ratification).

Allegations, however, that the Republicans have violated the Logan Act are misplaced. The Logan Act, passed during the Quasi-War with France near the beginning of the republic’s history, makes it illegal for any citizen “without the authority of the United States” to “carry on correspondence with a foreign government” to “defeat the measures of the United States.” Questions have been raised about the law’s constitutionality, with one court commenting that the terms “defeat” and “measures” were vague. In addition, the Senators styled their communication to Iran as an open letter rather than actually one being sent to Iran. Finally, senators and members of Congress would seem to have the “authority of the United States” since they are government employees, represent a co-equal branch of government, and need to communicate with foreign governments to exercise their “advice and consent” roles on treaties and their other plentiful powers in national security.

In sum, as much as limiting Iran’s nuclear program through negotiations is the only viable option (and the Republicans have suggested nothing better), upholding the spirit of the U.S. Constitution is more important; the Republicans are right in trying to force Obama to let them vote on any pact with Iran. Yet Republican attempts to sabotage negotiations with Iran before any agreement is reached—by breaching protocol and allowing Israeli Prime Minister Benjamin Netanyahu to make a campaign speech before Congress against such a pact and the aforementioned letter to throw a wrench into negotiations—are not only the wrong policy choice but undermine the spirit of the Constitution, which provides that the president should receive representatives of and negotiate with foreign countries.