Everybody is worked up about “extreme vetting,” and that’s fine, there’s a lot to be worked up about in the idea of a loyalty oath for all immigrants. Law professor Jonathan Turley did a good job of running through the history and the debate the other day in The Washington Post, concluding, somewhat surprisingly, that Trump “may have the law on his side” here.

I understand why liberals especially have a Pavlovian response to the phrase loyalty oaths, but I was far more troubled by the passage in Trump’s speech that came right after he improvised the “extreme vetting” remark. It went like this:

As soon as I take office, I will ask the State Department and the Department of Homeland Security to identify a list of regions where adequate screening cannot take place. We will stop processing visas from those areas until such time as it is deemed safe to resume based on new circumstances or new procedures.

The size of current immigration flows are simply too large to perform adequate screening.

We admit about 100,000 permanent immigrants from the Middle East every year. Beyond that, we admit hundreds of thousands of temporary workers and visitors from the same regions. If we don’t control the numbers, we can’t perform adequate screening.

This isn’t the first time Trump has said this. Maybe, in the context of all the other nuttiness that surrounded it, I just noticed it more. But it’s absolutely ghastly.

Think about it. His administration will identify “regions” where “adequate screening cannot take place.” And he’ll keep people out from those regions. Not just people who can’t answer loyalty-oath questions properly. Everyone.

Previously Trump has made the same claim about countries “compromised” by terrorism. What countries would that include? Well, let’s see. Certainly it would include France, doesn’t it? It’d be awfully hard to make the case that France isn’t “compromised” by terrorism. And to invoke Trump’s more recent criterion, it also seems pretty hard to argue that France has adequate screening.

So a Trump administration would ban immigration from France? Germany is pretty compromised. Ditto the United Kingdom. Israel? Please! And I don’t mean just Hamas. There are right-wing settler terrorist groups too. There is no way for American law to distinguish between Jewish terrorists and Arab ones. No way.

But here’s what’s really offensive about all this. Think in terms of three categories of people—terrorists, refugees, and everyone else.

Obviously, we all want to keep out terrorists to the extent that we can. With respect to refugees, I’d rather see us welcome in far more Syrian refugees than we are, but I get that they’re a politically controversial category.

But everyone else? Regular visa applicants?

David Leopold is an immigration lawyer in Cleveland. He told me Wednesday that he has a standard immigration law practice in many ways, which is to say that he handles a lot of deportation cases. But he also does some stuff that’s more unusual than that.

His clients include corporations and hospitals that want to bring over specialists from around the world. A hospital might want a highly regarded surgeon to come over here and open up a new program, he told me. Or a leading researcher to conduct a study. And sometimes, Leopold says, they’re from the kinds of countries Trump surely has in mind. “I’ve had many clients from Egypt, Syria, Jordan, Saudi Arabia, the UAE, and Lebanon,” Leopold told me. “Physicians coming over here to do critical research. He’s talking about doctors, he’s talking about engineers, he’s talking about artists, he’s talking about everybody.”

Here’s a complete list (Excel) from the Department of Homeland Security of immigration flows to the United States from every country in the world. Look through the numbers yourself. Country by country, they are not vast: Iraq, around 19,000 in 2014; Iran, about 11,000; Jordan, 5,500: Syria, 3,500; Lebanon, 3,200. But add them up, and then add in countries that aren’t in the Middle East but that nevertheless fit Trump’s description of being compromised. The Philippines, for example, which sent a hefty 50,000 people here in 2014.

And nearly all of these people are exactly the people we should want most. They’re desperate to come to America and get away from the turmoil. And people seeking green cards already jump through enormous hoops to come live here. If you are from Iran, Iraq, Syria, or Sudan in particular, it’s now tougher than ever to get here, ever since the government tightened some laws in January.

As usual, Trump doesn’t know what he’s talking about. He just wants to paint a picture of horror—of Obama not caring, of bureaucrats sitting around doing nothing, of sharia-loving hordes overrunning the customs outposts. He fosters, and counts on, ignorance. And into the bargain, he’d destroy our commerce with other nations, trade, scientific and technological research projects, educational relationships, cultural exchanges, everything.

He’s the one who needs to be extremely vetted.