On Monday, his first day back in office, President Donald Trump issued a wave of executive orders.

Some are ridiculous, such as an order purporting to rename the Gulf of Mexico the “Gulf of America.” Others are ominous, such as an order seeking to drastically increase the number of federal civil servants who can be fired at will. Many of the orders seek to implement the kind of harsh immigration policies that have always been at the heart of Trump’s political message.

The most alarming of these immigration orders seeks to strip millions of future Americans of their citizenship.

There isn’t even a plausible argument that this order is constitutional. The Constitution is absolutely clear that all people born in the United States and subject to its laws are citizens, regardless of their parents’ immigration status. The Supreme Court recognized this principle more than 125 years ago.

Nevertheless, Trump’s order, labeled “Protecting the Meaning and Value of American Citizenship,” purports to deny citizenship to two classes of Americans. The first is children born to undocumented mothers, whose fathers were not themselves citizens or lawful permanent residents at the time of birth. The second is children whose fathers have similar immigration status, and whose mothers were lawfully but temporarily present in the United States at the time of birth.

Almost immediately after this executive order was released, pro-immigration advocates started naming prominent Americans who might not be citizens if this order were in effect when they were born — including former Vice President Kamala Harris. That said, the order does not apply to current US citizens, and is not retroactive: It only attempts to deprive “persons who are born within the United States

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