The battle for control of America’s foreign policy goes back to the country’s founding.

When Speaker of the House John Boehner invited Israeli Prime Minister Benjamin Netanyahu to address a joint session of Congress on Tuesday, it was seen by many as an unprecedented politicization of American foreign policy. Wasn’t the president the guy in charge of that? Weren’t politics supposed to stop “at the water’s edge”?

In truth, however, Boehner’s insertion of the Republican-led Congress into the realm of international diplomacy and the Obama administration’s wounded accusations of partisanship obscured an ongoing tug-of-war regarding what role Congress should play in shaping foreign policy. Political scientists seeking some pattern based on principle would love to claim that one Party usually defers to the presidency, and the other to Congress. History shows, however, that even though modern Americans consider the President Mr. Foreign Policy, in Washington, partisanship has traditionally trumped principle. Whoever occupies the White House says the Constitution puts the president in charge, while those controlling Congress often trust Congress to lead.

The confusion comes from the Constitution itself: the Framers’ checks and balances mandated such messes. Having rebelled against England’s king and fearing presidential power, the Revolutionaries aimed for fragmented power and overlapping responsibilities. As a result, the Constitution empowered Congress to fund the government and to declare wars, which the president leads as Commander-in-Chief. Likewise, the Senate must approve treaties the president negotiates as chief diplomat.

Throughout the 19th and early 20th centuries, Congress and the president went back and forth in this ongoing Constitutional game of rock, paper, scissors. In 1812, the Canadian-hungry War Hawks, led by Henry Clay and John C. Calhoun, pushed a reluctant President James Madison into what became the disastrous War of 1812 that left the White House burning. In 1919, Senator Henry Cabot Lodge blocked Woodrow Wilson’s League of Nations. The senator accused the president of sacrificing America’s independence for the sake of empty ideals. “I have loved but one flag,” Lodge thundered, “and I cannot share that devotion and give affection to the mongrel banner invented for a league.”

In the swift switch from fighting fascism in World War II to fighting Soviet Communism during the Cold War, the president became the “Leader of the Free World” with his “finger on the nuclear button.”

During World War II, as “Dr. Win the War,” Franklin D. Roosevelt ushered in the modern era of the Extra-Strength Presidency, especially in foreign policy. Roosevelt’s masterful leadership during that bloody conflict concentrated foreign policy making power in the Oval Office. In the swift switch from fighting fascism in World War II to fighting Soviet Communism during the Cold War, the president became the “Leader of the Free World” with his “finger on the nuclear button.”

The prospect of nuclear Armageddon meant Cold War foreign policy was bipartisan and handled by the White House. Congressional Republicans had been the home of isolationists in the bitter fight during the 1930s over whether America should go to war against Nazi Germany and militant Japan, but Pearl Harbor, followed by revelations of Nazi war crimes, discredited the isolationists and encouraged a bipartisan approach that deferred to the Oval Office. Indeed, Republican Senator Arthur Vandenberg became the poster child for the reformed isolationist who believed that politics stopped “at waters’ edge,” meaning no partisanship in overseas matters.

The Vietnam War and the broader ’60s rebellion ended this bipartisan deference to the president, however. Motivated by principle, Congressional Democrats led the charge and opposed their own Democratic commander-in-chief, Lyndon Johnson, before turning on their Republican enemy, Richard Nixon.

During the 1970s, amid a backlash against what the liberal historian Arthur M. Schlesinger criticized as “The Imperial Presidency,” Congressional Democrats again tried to control American foreign policy. After the Paris peace accords in January 1973 ended the military conflict in Vietnam, Congress banned any funding for any combat activities anywhere in Indochina. As a result, when North Vietnam invaded in April 1975, President Gerald Ford was handcuffed. South Vietnam fell.

The Reagan Revolution that began in 1981 was yet another swing of the pendulum, allowing the president to seize power back from an increasingly powerful Congress. Boehner Republicans take note: Reagan learned from his political, if not ideological, role model FDR that the president must preside, especially in foreign affairs. Reagan’s restoration triggered bitter fights, especially over his attempt to foment a counter-revolution against the Soviet-supported Sandinistas in Nicaragua. As it had done in Indochina in the 1970s, Congress outlawed any money going to the Contras, this time with three provisions passed from 1982 through 1984 all collectively called the Boland Amendment. In 1973, Congress also passed the War Powers Resolution, reasserting its constitutional power to declare war by forcing the president to inform the Congress within 48 hours of any military action. This was in response to abuses by both Johnson and Nixon of the1964 Gulf of Tonkin Resolution, which they cited as authorization for the Vietnam War, but which fell short of the formal declaration of war the Constitution required.

Cowboy diplomats led by the charismatic Col. Oliver North ended up selling weapons to Iran, foolishly trying to free kidnapped Westerners and encourage moderates there. North then funneled the profits to the Contras. Torn between admitting guilt to what could have been an impeachable offense of defying a Congressional law and reinforcing impressions that he was losing it, Reagan punted. Twenty-eight years ago, on March 4, 1987, he admitting that his administration had traded “arms for hostages,” and explained his repeated denials: “My heart and my best intentions still tell me that’s true, but the facts and the evidence tell me it is not.”

The Reagan model held for nearly three decades. There were exceptions, true: President George H.W. Bush graciously turned to the Congress for support before entering the first Persian Gulf War in January 1991, for example. But the consensus in Washington seemed to be that the president decided, while Congress gave its advice and consent.

After January 1995, when Democratic President Bill Clinton faced a Republican Congress for the first time since the 1950s, his Republican rival Newt Gingrich expanded Congressional power, but mostly in domestic affairs. Gingrich may have built an imperial speakership, leaving Clinton to fume that he was still relevant, but the president at least kept control of foreign affairs. Even George W. Bush, despite his controversial foreign policies, did not endure the kind of Congressional committee torture Reagan endured with the Iran-Contra hearings.

This, then, is the improvised tradition Obama is defending and Boehner is challenging. It is extraconstitutional, with Congress deferring to the president more than the Framers intended. Its popularity among Democrats will probably last as long as they control the White House—just as Republicans will rediscover presidential prerogative when one of theirs moves back into 1600 Pennsylvania Avenue.