Marco Rubio grilled Rex Tillerson on the stand and says he has "serious reservations" about him. Yet he'll still vote to confirm him as secretary of state.

Remember two weeks ago when your friends were all amazed at Sen. Marco Rubio's gutsy showing at Rex Tillerson's confirmation hearing? After Rubio roasted the would-be secretary of state for refusing to call Vladimir Putin a war criminal, political columnists suggested he could become a GOP bulwark against Donald Trump's neglect for basic human rights.

Nah! Turns out Rubio will vote to confirm Tillerson anyway.

In a lengthy post on his Facebook page, Rubio lays out all of the very well-founded concerns he has about the former oil exec: Tillerson's refusal to condemn Putin, his unwillingness to commit to sanctions against Russia, his hesitation to call out human rights abuses by China, the Philippines, and Saudi Arabia.

So why would Rubio — a guy trying hard to lay claim to title of the "human rights defender" of the Senate — vote to support this guy? Well!

"I must balance these concerns with his extensive experience and success in international commerce, and my belief that the president is entitled to significant deference when it comes to his choices for the cabinet," Rubio writes. "Given the uncertainty that exists both at home and abroad about the direction of our foreign policy, it would be against our national interests to have this confirmation unnecessarily delayed or embroiled in controversy."

Here's an alternate theory: Rubio is a conviction-free ladder-climber who has never gone against what he believes his base wants.

The Tillerson vote isn't even the most egregious example this year.

Rubio was the loudest critic of Trump on the campaign trail — rightly so — until he got walloped in the primary, saw the winds shifting toward Trump in Florida, and then suddenly announced he would vote for the guy he had just recently called a "con man," "dangerous," a "strong man," and "catastrophic."

Then there was Rubio's famed tweet in May that "I have only said like 10000 times that I will be a private citizen in January," which was true right until he realized the GOP field was weak-sauce enough that he could stroll back into power.

Rubio has been consistent since his rise as a mainline Jeb Bush prodigy to a Tea Party-baiting outsider to a Trump-appeasing apparatchik. He's gonna do whatever keeps himself in power. Don't forget it.

