Sen. Jeff Flake could have demonstrated the principled leadership he has preached in his waning days of relevancy in the U.S. Senate, but when push came to shove, Arizona’s outgoing Republican senator chose his party over his country and voted to appoint Brett Kavanaugh to the U.S. Supreme Court.

At several times during the rushed and incomplete confirmation process, Flake stood as a moral speed bump, urging his colleagues to hear testimony from a woman, Christine Blasey Ford, who said that Kavanaugh had sexually assaulted her at a party when they were both in high school.

Kavanaugh denies the assault.

After the allegations became public, Flake made a speech on the Senate floor, urging his colleagues to keep open minds, to listen to Ford and Kavanaugh give testimony before the Judiciary Committee:

“When Dr. Ford came forward, I felt strongly that her voice needed to be heard, and that is why I informed Chairman Grassley that the Judiciary Committee could not and should not proceed to vote until she had the opportunity to make her voice heard, until such time that her claims were fully aired and carefully considered, her credibility gauged. This is a lifetime appointment. This is said to be a deliberative body. In the interest of due diligence and fairness, it seemed to me to be the only thing to do.”

After the testimony, and after he said he’d vote for Kavanaugh, Flake was confronted in an elevator by sexual assault survivors.

He decided to ask for an FBI investigation into the allegations, which made sense — but would have been more meaningful if Flake had not limited it to a week.

Instead, the Senate’s Republican majority continued to push an artificially rushed confirmation process.

The FBI’s document has not been made public.

Both sides say the report does not verify Ford’s allegation, but Democrats say it was a narrow investigation and some potential witnesses were not interviewed.

Kavanaugh’s performance during his Senate testimony last week made it clear that he is not qualified for the U.S. Supreme Court, apart from whether one believes Ford’s account.

Kavanaugh’s seething countenance and vituperative political conspiracy theories — this was all a plot by Democrats and payback from the Clintons for his work with special prosecutor Ken Starr — painted a vivid picture of a partisan without the even keel needed to weigh and rule on the often politically charged and emotionally freighted cases that reach the Supreme Court.

Kavanaugh has since written in the Wall Street Journal that he shouldn’t have said some of the things he did during the hearing. That’s not good enough.

It is understandable, and appropriate, that a president seeks to appoint a Supreme Court justice whose interpretation of the law aligns with his or her own.

Those who view the law differently can make arguments also rooted in law.

It is the Senate’s duty to weigh the candidate and decide on confirmation. Senators must not be a rubber stamp, or a rubber stamp on a brief time delay.

Flake has abandoned his duty.

With his vote to confirm Kavanaugh he has made himself complicit in dishonoring the role and integrity of the Supreme Court.

The Republicans’ quest to pack the high court with right-wing conservatives has won out.

We had expected more from Flake, who has made headlines for his rhetoric, refusing to support Donald Trump during the 2016 and rebuking the president for his lies, his attacks on the free press, attacks on Attorney General Jeff Sessions, and more.

Kavanaugh is very much Trump’s candidate.

The president has bolstered Kavanaugh, speaking of a kinship he feels because he, too, has been accused of sexual assault. Trump has mocked Ford at his public rallies, using her as a punch line for laughs.

In this moment we’re reminded of the late Sen. John McCain, who used his thumbs-down vote to tank rushed legislation to gut the Affordable Care Act. His was an act of courage.

Flake said Friday that “unless something big changes” he would vote for Kavanaugh — and he did.

It was too much to hope that “something big” would have been Sen. Jeff Flake finding his backbone to vote against the appointment of Brett Kavanaugh to the Supreme Court.

Flake let Arizona down, again.