What did Donald Trump do today?

He confirmed that he'd ordered the arrest and deportation of a lawful permanent resident for holding political beliefs he doesn't like.

Yesterday, immigration officials arrested Mahmoud Khalil in New York and began attempting to have him deported. Khalil has a green card, meaning he is a legal permanent resident of the United States. Under all but the most extraordinary circumstances, he cannot be deported, and certainly not without extensive legal processes.

Khalil is the husband of an American citizen who is pregnant with his child. His family were not told where he was after his arrest, and were forced to resort to the extraordinary legal remedy of a habeas petition. It was eventually determined that he had been sent to a prison in Louisiana—but only after his lawyers had begun to ask about his whereabouts.

Today, possibly in an attempt to cover up the fact that Khalil had been arrested mistakenly on a false tip that he was overstaying a student visa, Trump announced in a post on his boutique social media site that ICE had "proudly" arrested Khalil, whom he called a "Radical Foreign Pro-Hamas Student." Trump also said that "This is the first arrest of many to come."

In a separate release tauntingly titled "Shalom Mahmoud," the White House claimed that Khalil's leadership of anti-genocide protests on Columbia's campus meant he was "aligned with Hamas." Secretary of State Marco Rubio confirmed that the Trump administration would "be revoking the visas and/or green cards of Hamas supporters in America so they can be deported."

Under the First Amendment, it is not a crime to "be aligned with" Hamas or anyone else—not even, for example, neo-Nazis or white supremacist militias. More to the point, Trump says that kind of thing about anyone who disagrees with him. He said that Sen. Chuck Schumer, who is Jewish, was a "proud member of Hamas" because Schumer opposed Trump's ethnic cleansing plan for Gaza.

A federal judge blocked the deportation order today. Khalil remains in custody but has not been charged with any crime. A huge crowd formed at the site of his arrest today, protesting his treatment. 

Trump has not commented on whether the people protesting in support of Khalil's civil and constitutional rights were also subject to arrest and deportation for their political "alignment."

Why does this matter?

• Saying things the president doesn't like isn't a crime or a deportable offense, because the president is not a king.

• Being arrested without charge for political speech the ruler finds threatening is what happens in a dictatorship.

• Nobody really thinks this is about Trump's deep and abiding commitment to fighting anti-semitism.