MANILA (PHILIPPINE DAILY INQUIRER/ASIA NEWS NETWORK) - Almost every president talks about the crushing burden of the office; only President Duterte talks frequently about giving it all up, and with an obvious sense of frustration.

But from the many words he has said on the unusual subject, and especially from his most recent remarks, it is clear that one thing, and one thing alone, is stopping him: the Constitution.

Is the President serious and sincere about stepping down?

Many in the political class, both those allied with him and those opposed to him, do not believe that his statements should be taken at face value.

Even his own spokesperson, Harry Roque, describes the President's expression as just a "statement of exasperation."

But he has expressed his wish to step down many times.

Last Tuesday, when he unburdened himself before entrepreneurs gathered in Malacanang, he looked particularly pained.

"I want you to know that I am thinking of stepping down because I'm tired."

(He said this was the gist of his message to a recent command conference with the leaders of the uniformed services.)

He also said: "… my chase against graft and corruption seems to be endless and it has contaminated almost all government departments and offices."

And then: "I do not think that I can fulfill my promise to the people… I said I will try to stop corruption, which I'm doing. And still, I cannot succeed even beyond my term."

Even if only on these specific terms, the country must seek to understand what is it exactly that the oldest president elected to office wants to say, and why he is saying it.

Is he creating yet another distraction, from yet another billion-peso shabu smuggling scandal?

He says the Philippine Drug Enforcement Agency's conclusion - that the empty magnetic lifters intercepted contained P6.8 billion (S$174.9 billion) worth of shabu - was "speculation."

Is he sounding the call to his political base, to gather round him at a time when his once-stratospheric popularity ratings have been pulled low?

Senator Manny Pacquiao, one of the very few to say in public that he believes the President really wants to resign, has responded to the President's frustration by pledging ever greater devotion.

Is the President indulging his old habit of evoking pity from his constituents, because that's an effective habit he has never had to break?

Unlike previous statements, last Tuesday's remarks were intriguingly specific and detailed.

He does look tired, frustrated, at the end of his rope.

Assuming he is serious and sincere about stepping down, what stops him from following through and resigning?

He explains it himself: "I am hesitant to suggest a constitutional succession. I have nothing against (Vice President Leni) Robredo. She's a lawyer, you have heard her talk, but I do not think she can improve on anything here."

But the President is not in a position to suggest any such thing.

The Constitution itself orders that if a president dies in office or resigns or is incapacitated, he or she shall be immediately replaced by the incumbent vice president.

For President Duterte to assert that the constitutional process of succession is a mere suggestion contravenes both the Constitution and the democracy that the founding law constituted.

In the same forum, the President said that he has shared a succession scenario with security officials.

"If you say, President, sir, we find you not at par or not in parity with the expectations, and you say, We have found a leader, I will step down."

In other words, he has invited the military and the police to form an unelected junta to choose a leader other than Robredo.

This is not only unconstitutional and undemocratic; it is also deeply unfair to the armed services, especially the military, which has learned to professionalise itself at great cost and over a long period of time.

He is inviting the Armed Forces to betray its own role as protector of the people and the state - and for what?

To prevent Robredo from succeeding him.

On the other hand, he also said last Tuesday that he would step down if defeated vice presidential candidates Bongbong Marcos and Chiz Escudero would replace him.

(He forgot to mention his own running mate, Foreign Secretary Alan Peter Cayetano-surely a personal insult.)

Are these gentlemen demonstrably better, more competent, than Robredo?

The constitutional provision on succession says the answer does not matter.

The Vice President succeeds the President - and the professional and patriotic military knows that.