He knows

President Donald Trump wasn’t planning to attend the recent National Rifle Association convention — that is, until he learned that Vice President Mike Pence would be giving the keynote address.

That led to a change of plans in the West Wing, according to two people familiar with the arrangement, and nearly a week after the NRA announced Pence would speak, the president was added to the schedule to speak moments after Pence.

It wasn’t the first time Trump has changed his plans to one-up the veep. It was originally Pence, not Trump, who planned to travel to the World Economic Forum in Davos, Switzerland. But upon seeing who else would be attending, Trump decided to make the trip himself instead, bumping Pence off the schedule, according to a person familiar with the matter. A White House official said that neither scheduling decision was based on the vice president’s plans.

[...]

Pence’s team has worked assiduously to dispel any rumors that Pence might be harboring his own ambitions for the Oval Office, even as Pence hired a political operator as his chief of staff and formed a leadership PAC to support Republican congressional candidates.

But that hasn’t stopped the president from going out of his way to make sure Pence stays in his shadow.

  Politico

Can the president fire the vice president?

...but hey, do what you want...you will anyway.