House speaker Paul Ryan announced on Thursday that he would after all vote for Donald Trump, the presumptive Republican presidential nominee.

Ryan, the most powerful elected Republican in the country, refused to endorse Trump last month, even after the businessman’s two remaining rivals had suspended their presidential bids.

He had also broken with precedent during the primaries to criticize Trump when the latter proposed to temporarily bar all Muslims from entering the United States. “[This] is not what this party stands for and more importantly it’s not what this country stands for,” Ryan said at the time.

Now he maintains that he has “more common ground than disagreement” with Trump.

Ryan writes in a local newspaper in his home state of Wisconsin that private conversations with Trump have convinced him that the New Yorker would support his legislative agenda as president.

Which, if he’s honest, either means Ryan has changed his mind on major issues or Trump told him something different in private than what he says in public.

What common ground?

Ryan lists several priorities: a better tax code, repealing and replacing Obamacare, halting executive overreach and national security.

On none of those issues has Trump outlined truly conservative policies, if he has outlined policies at all.

Trump’s idea of tax reform is lower rates for millionaires and billionaires like himself. That’s been part of Republican tax plans for decades, but absent from Trump’s proposal is relief for low-income families, something Ryan advocates.

Trump has promised to repeal Barack Obama’s health reforms and replace them with “something terrific.” His official plan, available online, includes such long-standing Republican policies as block-granting Medicaid spending to the states and allowing Americans to deduct health insurance costs from their taxes.

But Trump has struggled to describe “his” plan in public and ruffled right-wing feathers by saying, “I am going to take care of everybody.”

As for executive overreach, Trump is the last person who would restore humility to the presidency. His entire campaign is based on the idea that he, the man, can “make America great again.” He has shown no respect for the separation of powers nor any patience for the constitutional restraints on the office he seeks, promising, among other things, to “open up” libel laws to prosecute journalists, remove a judge in the case against his fraudulent Trump University because he’s “Mexican” (he isn’t) and force the military to commit war crimes.

Dangerous

When it comes to national security, Trump is not just alarmingly ill-informed; his attitude — never forgive; always get even; if somebody hits you, hit them back ten times harder — is dangerous.

Hillary Clinton, Trump’s likely Democratic opponent, warned on Thursday, “He is not someone who should ever have the nuclear codes, because it’s not hard to imagine Donald Trump leading us into war just because somebody got under his very thin skin.”

If that weren’t bad enough, Trump has singlehandedly repudiated decades of Republican foreign-policy thinking.

He has criticized the Iraq War, even though he supported it in 2002. He believes he would get along better with the Russian president, Vladimir Putin, than with Britain’s prime minister, David Cameron, because the latter criticized his proposed Muslim ban. He rejects free-trade deals; he has said NATO is outdated and Israel, Japan and South Korea should all fend for themselves, even if that means them getting nuclear weapons.

So when Ryan says he has found “common ground” with Trump, does anyone know what he’s talking about?