The courts are doing it. President Trump is doing it. So why can't we? Let's argue about whether Trump's travel ban on seven predominantly Muslim countries is legal, using some of the very arguments heard in a San Francisco federal appeals courtroom this week. Those judges are preparing to make a ruling that could decide its fate.

Baraah Alawdi, originally from Yemen, poses for photos next to an unidentified artist's mannequin placed outside of the 9th U.S. Circuit Court of Appeals in San Francisco. (AP Photo/Jeff Chiu)

1) On whether the ban has precedent

If you agree with the ban, say: In 2015, Congress designated these seven countries on Trump's list as having problems with terrorism.

If you disagree with the ban, say: Those countries had restrictions on visa waiver programs — not travel bans — and some top congressional Democrats didn't agree with even that limitation, because they thought it relied too heavily on a person's nationality.

2) On whether the ban can save lives

If you agree with the ban, say: Well, quote the president. That's basically what the Justice Department lawyer did when 9th Circuit Court judges asked him that question.

If you disagree with the ban, say: There is no direct evidence tying any of these countries to terrorism. Plus, the government already screens people from these countries who want to enter the U.S. “Is there any reason for us to think that there’s a real risk or that circumstances have changed such that there’s a real risk?” asked Judge Richard Clifton, a Bush appointee.

3) On whether the ban is an unconstitutional religious test

If you agree with the ban, say: The vast majority of Muslims would not be affected by this, as Clifton also pointed out.

If you disagree with the ban, say: Or point, rather, to former New York mayor Rudy Giuliani, a Trump adviser, who recently said a religious test is what the president wanted :"[W]hen Trump first announced it, he said, ‘Muslim ban.’ He called me up. He said: ‘Put a commission together. Show me the right way to do it legally.’ ” During the campaign, Trump also often used the term “Muslim ban.”

You'll never guess what side Trump comes down on all this

Nobody expects Trump to be rooting for the courts to knock down his ban. It is, after all, his signature policy achievement so far, meant to make good on a signature campaign promise to get tough on terrorism.

But Trump isn't just sharing his opinion on the ban with us. He's not-so-subtly threatening the entire American court system if they don't side with him, including the above comment he made Wednesday in a speech to law enforcement. Also, he's tweeted a lot about this.