Alien Enemies Act Allowed Deportation, Not Imprisonment in Foreign Country

"The Naturalization Act of 1798 increased the requirements to seek citizenship, the Alien Friends Act of 1798 allowed the president to imprison and deport non-citizens, the Alien Enemies Act of 1798 gave the president additional powers to detain non-citizens during times of war, invasion, or predatory incursion, and the"

https://www.archives.gov/milestone-documents/alien-and-sedition-acts

So are laws against theft and murder.

How do you know they are non-citizens?

I wouldn't know as I cannot check their paperwork :P
US citizens have a SSN, birth certificate, and other paperwork the government can look up. But in the end it is up to the government to prove they are not citizens.

This is precisely WHY we have DUE PROCESS

This government feels they don't have to prove anything.

You're making stuff up for them to believe and attacking your own imaginary monsters.

"imprison and deport non-citizens"

NOT Deport then imprison in a foreign country

There's precedent.

Yes