There’s a process to remove incapable presidents, but it probably won’t be used on Trump — yet

John F. Kennedy’s assassination in November of 1963 exposed some awkward flaws in the U.S. constitution.

Vice-President Lyndon Johnson was sworn into the presidency at the Dallas airport by a Texas judge (a moment captured by an iconic photograph.) But the constitution didn’t help answer some crucial questions: How, exactly, does a vice-president become president? How would a new vice-president be chosen? What if Kennedy hadn’t been killed, but wounded in a way that made it impossible to carry out his duties?

Earlier ages had been content to let these questions rest.

Woodrow Wilson, for example, suffered a stroke in October of 1919, and some historians believe that the presidency was largely carried on by Wilson’s wife Edith for the next year and a half. Franklin D. Roosevelt’s illness was kept rigidly secret until his death in April of 1945. (Vice-President Harry Truman, who had to fill FDR’s shoes, had been given no preparation at all — he didn’t know about the U.S. atomic bomb program until two weeks after Roosevelt’s death.)

A slower-paced age could work around these situations, but with the high-stakes nuclear decision-making of the Cold War, much more formal rules were needed.

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Kennedy’s death forced Congress to do something about it. The 25th amendment to the constitution dealt with succession issues, and also laid out rules for what would happen if a president was”unable to discharge the powers and duties of his office.”

The amendment’s longest clause deals with a situation where the people around a president felt he was incapable, but he disagreed. Here’s how it begins:

• Whenever the Vice-President and a majority of either the principal officers of the executive departments (cabinet members) or of such other body as Congress may by law provide, transmit to the President pro tempore (speaker) of the Senate and the Speaker of the House of Representatives their written declaration that the President is unable to discharge the powers and duties of his office, the Vice-President shall immediately assume the powers and duties of the office as Acting President.

In other words, if U.S. Vice-President Mike Pence and at least eight of the 15 members of the U.S. cabinet were willing to depose Donald Trump, they could do it, and Pence would become acting president on the spot. (Bear in mind that Donald Trump named all the members of his cabinet, and if he sensed a plot against him, he could fire them and replace them with loyalists.)

READ: Could Donald Trump’s firing of James Comey lead to impeachment?

“Unable to discharge the powers and duties of his office” is a very open-ended phrase. It could cover physical or mental illness, but arguably could be stretched to cover a president’s catastrophic issues with judgement or competence, in extreme cases. What it means in any given situation is left open to the people making the decision.

“Or of such other body as Congress may by law provide”: Congress has never acted on this provision, but a Democratic congressman, Earl Blumenauer, recently introduced a bill to provide for a sort of council, made of of living former presidents and vice-presidents of both parties, who would decide if a president was so unfit for office that he should be deposed.

Where it all gets messy is if the president pushes back:

• Thereafter, when the President transmits to the President pro tempore of the Senate and the Speaker of the House of Representatives his written declaration that no inability exists, he shall resume the powers and duties of his office unless the Vice-President and a majority of either the principal officers of the executive department or of such other body as Congress may by law provide, transmit within four days to the President pro tempore of the Senate and the Speaker of the House of Representatives their written declaration that the President is unable to discharge the powers and duties of his office.

In other words: if the president wants his job back, he tells Congress, and the vice-president and cabinet members who want him deposed have four days to tell Congress that they still want to proceed with deposing him. (We can imagine the drama of these four days; the suspended president could no longer fire the cabinet members that turned on him, but pressure on a few of them might bring the total below eight votes. On the other hand, if the process failed at this stage, the president would have no way of getting rid of a plotting vice-president, who is an elected official in his own right.)

• Thereupon Congress shall decide the issue, assembling within forty-eight hours for that purpose if not in session. If the Congress, within twenty-one days after receipt of the latter written declaration, or, if Congress is not in session, within twenty-one days after Congress is required to assemble, determines by two-thirds vote of both Houses that the President is unable to discharge the powers and duties of his office, the Vice-President shall continue to discharge the same as Acting President; otherwise, the President shall resume the powers and duties of his office.

WATCH: House Minority Leader Nancy Pelosi was asked about the case for impeachment on President Trump saying, “it’s very hard.”

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So if a president wants to continue in office, he will, unless there is an overwhelming consensus in both parties in both houses of Congress, and in the administration that he himself chose, that he needs to be forced out.

It’s a very, very high standard to have to meet. But it’s easy to see what the framers of this clause were trying to do — presidents mostly enter office with a high level of democratic legitimacy, and all of them with constitutional legitimacy. Undoing the voters’ decision might be necessary, but only as a necessary evil in response to an extreme crisis. It also puts the process out of reach of being abused by a Congress that is controlled by the opposite party from the president.

The impeachment process is designed to give a president accused of real crimes a chance to defend himself, as he would be able to in a courtroom. “Inability” is a more subjective standard, and so the framers seem to have compensated by setting a higher bar for removing a president than for impeachment (a simple majority in the House to start the process, and a two-thirds majority in the Senate to convict).

READ: Why a ‘nuclear mutiny’ against a President Donald Trump would likely fail

In the first few months of his administration, Donald Trump has lurched from crisis to crisis to crisis to crisis. He has seemed profoundly, and publicly, out of his depth on many levels.

(His White House has not yet been tested by a crisis external to itself, but it is certainly coming, as real crises have happened to all his predecessors.)

Can his administration continue until January 20, 2021, which is (at the time of writing) 1,345 days, or 3.6 years, from now?

Or will it continue, but in a less accident-prone way?

That would be nice to imagine, but Trump is, for better or worse, Trump. He is 70 years old, set in his ways, and, conservative commentator Erick Erickson writes, ” … he does not want advice, cannot be corrected, and is too insecure to see any constructive feedback as anything other than an attack.”

So many (not many Republicans, at least in public) have started exploring impeachment, or removal under the 25th Amendment. The conversation is a bit theoretical, not least because Republicans control both houses of Congress.

That’s not going to change before midterm elections in 2018, in which Democrats may get the seats they need in the House to start an impeachment process, but are unlikely to get the Senate seats they would need to complete it, unless a significant number of Republicans start supporting impeachment.

So will we see any of the constitutional machinery for removing a president rumbling into action?

It’s hard to see it happening, unless the medium-sized crises get so much worse, or a really big crisis is so mishandled, that a critical mass of Republicans see Trump’s removal from office as a matter of self-preservation or decide to support it as a matter of patriotism, or some combination of both.

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