With Donald Trump now officially the president, his opponents are talking more than ever about the hypothetical ways to remove a chief executive from power.

One of those potential tactics would be to remove them from the White House due to mental or physical incapacity.

While there's no evidence that Trump has any illness that would prevent him from carrying out his duty, if he ever did, the Constitution provides a way. However, it's extremely complex, and would require him to be either totally unable to do the job, or have his Vice President, cabinet, and Congress revolt.

This hypothetical scenario is addressed in Section 4 of the 25th Amendment, which lays out a complex procedure for how to sideline a president who is "unable to discharge the powers and duties of his office."

For the vast majority of United States history, there was no law regarding how to replace an incapacitated president or name a new vice-president.

This led to a number of long stretches with no VP, as well as first lady Edith Wilson essentially running the country for 18 months after President Woodrow Wilson's severe stroke in October 1919. It wasn't until 1957, in the wake of a more mild stroke suffered by Dwight Eisenhower, that the ground started to be laid for changing the law.

After the Kennedy assassination and fearing loss of governmental continuity after a Soviet nuclear strike, Congress and the states ratified the 25th Amendment. It clarified Article II, Section 1, Clause 6, and laid out the particulars of presidential succession.

The amendment formally codifies that the vice president becomes head of state after the president's death or removal (the so-called "Tyler Precedent"); that the president can nominate a new vice president to be confirmed by Congress; and that the president may temporarily abdicate their duties to the vice president.

All three of these provisions have been invoked. Section 1 was tested after Richard Nixon's resignation; two vice presidents have been confirmed under section 2, and there have been several instances of presidents briefly transferring power while undergoing anesthesia. The West Wing also invoked section 3 several times.

But section 4 of the 25th Amendment, concerning the removal of a president who is incapacitated, has never been invoked. It details the process for removing a president from power if the vice president and a majority of the cabinet believe the president to be mentally incapacitated or unbalanced.

They can declare the president disabled by submitting a written declaration to the president pro tempore of the Senate and the speaker of the House. The vice president would then become acting president, with the responsibility that comes with the highest office.

If able, the president can submit their own declaration that he or she is, in fact, mentally fit for the office. But even then, they wouldn't simply get their position back. The vice president and majority of the cabinet could declare that they still believe the president to be unfit - keeping the vice president as acting president.

The matter then would go to Congress, which would have to vote within 21 days. If two-thirds of both the House and Senate agree that the president is incapable of holding the office, the vice president would permanently continue as acting president. If the vote fails, or no decision is reached, the president resumes their duties.

Even if the vice president continues as acting president, the president could submit another declaration of his mental fitness, which would force the vice president and cabinet to go back to Congress for another vote. Theoretically, this could continue indefinitely, as the 25th provides no limit on how many votes can be taken.

In theory, this could result in either a successful coup (if Congress is in on it), a foiled coup (if they aren't), or a truly unwell and incapacitated president being removed from office.

So will Trump spur the first instance of section 4 being invoked? Unless something like a devastating medical incident or complete nervous breakdown occurs, almost certainly not.

With a Republican president comes a Republican vice president and cabinet the president has picked — people with little incentive to remove the man who made them and throw their party in turmoil. A removed Trump would likely fight hard to keep his powers, and section 4 has never been tested in court. And conservative pundits have called the outcry to remove Trump with the 25th at best misguided, and worst, deranged.

But if Mike Pence and Trump's cabinet were able to rally their party around the idea of removing Trump from office for the sake of the country, they could potentially sideline him for his entire term, with Pence stepping in as acting president, and Trump having little recourse. It's extremely unlikely to happen, but it's there - waiting for someone to try it.