I have previously criticized Texas’s badly flawed argument that illegal immigration and cross-border drug smuggling qualify as an “invasion,” thereby triggering the state’s constitutional authority to “engage in war” in response (see also here). Prominent legal scholars Frank Bowman (Univ. of Missouri) and Steve Vladeck (Univ. of Texas) have recently posted articles on the same topic, at Just Security and Lawfare, respectively.
Bowman offers a detailed originalist critique of the invasion argument, surveying a number of relevant founding-era sources:
I discussed the original meaning of “invasion” here, highlighting (among other things) James Madison’s unequivocal statement that “Invasion is an operation of war.”
Vladeck recognizes (correctly, I think), that an attack by nonstate actors could qualify as an invasion, but notes that does not mean illegal migration does:
Both Bowman and Vladeck make many good points. Both articles reading for anyone interested in this issue!
I don’t fully agree with all of their arguments. Most notably, I am not sure I am convinced by Vladeck’s claim that a federal statute could override a state’s right to engage in war even in a situation where the state really is facing an invasion. But that issue does not arise in a situation where supposed invasion is really just some combination of illegal migration and smuggling.
Whatever the right policy response to these challenges (I think it’s to make legal migration easier and to end the War on Drugs), their existence doesn’t authorize a state to wage war, or the federal government to suspend the writ of habeas corpus. Under the Constitution, both of these extreme measures would be permissible if there really was an invasion.