A revised and updated version of my article "Immigration is Not Invasion" now up on SSRN and can be downloaded for free. It would also enable state governments to initiate war without federal authorization. This article makes the first comprehensive case against claims that illegal migration and drug smuggling qualify as "invasion." Part II explains why the broad interpretation of "invasion" is manifestly wrong under the text and original meaning of the Constitution. Finally, Part V explains why courts should not defer to the president or to state governments on either the meaning of "invasion" or the factual issue of whether an "invasion" – properly defined – has actually occurred.