What did Donald Trump do today?

He said he would ignore the Constitution to deport American citizens.

In an interview with NBC's Meet The Press, Trump said this morning that he would "have no choice" but to deport children who were American citizens along with undocumented family members.

In reality, and under the actual laws of the United States, no President has the "choice" to expel American citizens from the country at all, under any circumstances.

Trump also said that he would use executive orders to change the definition of an American citizen to exclude those born in the United States to undocumented parents. 

Again, the Fourteenth Amendment defines who is a citizen, not Donald Trump, and neither a presidential memo nor even a law can change that. The first sentence of it reads "All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside."

During his first term, Trump made a point of advertising cruelty to migrant children, separating them from their families during processing and keeping them in what amounted to open-air prisons. But he's not completely opposed to bending the rules on immigration: both his first and third wives violated immigration law before marrying him and obtaining citizenship that way—Ivana Trump by engaging in a sham marriage that let her enter the U.S., and Melania Trump by working illegally on a tourist visa. Melania Trump then sponsored her own elderly parents' citizenship application, which Trump rushed through in spite of condemning "chain migration" when other families do it. 

The four of Trump's five children born to those wives would still retain their citizenship under his proposed policy, since he was a citizen. But the late Ivana Trump and Melania Trump could have their citizenship revoked for illegally working in the United States—as could, among others, Trump's benefactor Elon Musk.

Why does this matter?

• The Constitution is the supreme law of the land, not what a president feels like it should be. 

• It's bad when the very rich and very powerful don't have to obey the law.