One of the interesting tidbits that can be found in the government’s defense of President Trump’s Muslim Ban is the argument that it may very well violate the law to discriminate in the issuance of immigrant visas “based on nationality, place of birth, or place of residence” but that this cannot prevent the president from denying people with validly issued visas entrance based on a discriminatory criteria. The Justice Department lawyers may well be correct in this, and I think hashing it out may be key to deciding the short-term fate of the ban.

It seems pretty clear that the people working in consular affairs who handle visa applications have to operate under a restriction that was introduced by a 1965 amendment to the Immigration and Naturalization Act of 1952. That amendment contains the quoted language above that prohibits discrimination based on nationality and residence.

Yet, that amendment only addresses the issuance of visas. The 1952 law says the following about the president’s powers:

Whenever the president finds that the entry of any aliens or of any class of aliens into the United States would be detrimental to the interests of the United States, he may by proclamation, and for such period as he shall deem necessary, suspend the entry of all aliens or any class of aliens as immigrants or nonimmigrants, or impose on the entry of aliens any restrictions he may deem to be appropriate.

In other words, the president can deny you entry into the country even if you have a legal visa, and he can do it simply by determining that you (and everyone kind of like you) are detrimental to the interests of the country. If that determination is based on the president’s personal animus towards you (and everyone kind of like you), that seems to be sufficient. There’s nothing in the law about the president’s determination being fair or even sane. He can do it even if it he can’t sign a constitutionally valid law or issue a constitutionally valid order forcing our consular officers to stop issuing the visas.

Based on the language of the law, the president doesn’t need to pretend that there is a national security rationale for his actions, so judges cannot review the rational basis for his decisions.

That, at least, is what the DOJ lawyers are arguing.

And they could very well win the day for a pretty simple reason, which is that we have a presumption that our president won’t behave in the way Trump is behaving. Ordinarily, a president wouldn’t ban entry to people in the absence of a credible national security threat based on actual intelligence. He and his advisers would not nakedly admit that their motivations are based on criteria that are only tangentially and weakly tied to national security, and that are formulated on idiosyncratic and contentious beliefs about threats that may develop in the future and over a long period of time.

In this case, the administration’s fear is that Muslim immigration is an incremental threat, as each new Muslim (in their minds) adds some small degree of lone wolf threat, and that allowing a lot of Muslim immigration may eventually result in large, disaffected Muslim communities that breed internal dissent and possible acts of terrorism.

They make these arguments in nonlegal settings, like speeches and interviews, but they know better than to make them as legal arguments. Here is how Rudy Giuliani explained their process on Fox News:

“Okay. I’ll tell you the whole history of it. So when [Trump] first announced it he said, “Muslim ban.” He called me up and said, “Put a commission together, show me the right way to do it legally.” I put a commission together with Judge Mukasey, with Congressman McCaul, Pete King, a whole group of other very expert lawyers on this. And what we did was we focused on, instead of religion, danger. The areas of the world that create danger for us. Which is a factual basis. Not a religious basis. Perfectly legal, perfectly sensible, and that’s what the ban is based on. It’s not based on religion. It’s based on places where there are substantial evidence that people are sending terrorists into our country.

Now, Giuliani is still wrong in the particulars, because the government hasn’t presented any evidence (substantial or otherwise) that the seven impacted countries in the Muslim Ban were selected because they’re sending terrorists into our country, and countries that have sent terrorists into our country in the past were left off the list. But this quibble may have little legal value if the president can act on his own say-so without any justification whatsoever. In fact, according to the government’s argument, it was unnecessary to even put “danger” into the mix.

There’s a political reason to argue that the policy is based on danger, of course, but that’s a separate issue. Yet, even here, the danger argument is mischaracterized. They haven’t identified a specific and imminent danger. They believe in a theoretical danger.

Trump’s top advisors on immigration, including chief strategist Steve Bannon and senior advisor Stephen Miller, see themselves as launching a radical experiment to fundamentally transform how the U.S. decides who is allowed into the country and to block a generation of people who, in their view, won’t assimilate into American society…

…The chief architects of Trump’s order, [Steve] Bannon, [Stephen] Miller and National Security Advisor Michael T. Flynn, forged strong bonds during the presidential campaign.

The trio, who make up part of Trump’s inner circle, have a dark view of refugee and immigration flows from majority-Muslim countries, believing that if large numbers of Muslims are allowed to enter the U.S., parts of American cities will begin to replicate disaffected and disenfranchised immigrant neighborhoods in France, Germany and Belgium that have been home to perpetrators of terrorist attacks in Europe in recent years.

Within decades, Americans would have “the kind of large and permanent domestic terror threat that becomes multidimensional and multigenerational and becomes sort of a permanent feature,” one senior administration official argued.

“We don’t want a situation where, 20 to 30 years from now, it’s just like a given thing that on a fairly regular basis there is domestic terror strikes, stores are shut up or that airports have explosive devices planted, or people are mowed down in the street by cars and automobiles and things of that nature,” the official said.

So, the legal battle is really over the administration’s right to act in a radically experimental and discriminatory manner based on their “dark view of refugee and immigration flows from majority-Muslim countries,” and not on any specific terror threat or tangible or imminent “danger.”

We’ll find out if the law is on their side. It is quite possible that it is.

It would be a shame if it is, and one more example of how Donald Trump is finding and exploiting weaknesses in a system that is less robust in protecting the weak and vulnerable than we had hoped and expected.