Lord I hope not. That would imply they know they have already let them in.
Hope not? Me, too. They admit to over 8 million coming in, virtually all unscreened. The uncounted gotaways, totally unscreened, probably bring the total to 10 million. If 1/2 of 1 percent are terrorists, how many is that?
Sounds to me like guaranteed success for a number of terrorists.
Record Number of Suspected Terrorists Crossed the U.S.-Mexico Border | Opinion 10/28/22 (year old article)
And of course they only know about a fraction of those who enter illegally.