Well on the one hand you have to draw the "customs/immigration enforcement" line somewhere. And "defense in depth" certainly makes as much sense in the real world as it does in computer security.
But on the other hand I don't see a way for this to actually appreciably positively affect U.S. border security without stripping away most of what it means to be an American at all.
Even random checks at a high enough interval to give a good chance at making it too risky to attempt a terrorist plot would be tremendously impacting on day-to-day life. The effect of the DHS would be much more severe than the effect of any supposed terrorists themselves!
Better instead to use any such resources on things more beneficial to the common welfare, and to get rid of the extraneous legal authority.
But on the other hand I don't see a way for this to actually appreciably positively affect U.S. border security without stripping away most of what it means to be an American at all.
Even random checks at a high enough interval to give a good chance at making it too risky to attempt a terrorist plot would be tremendously impacting on day-to-day life. The effect of the DHS would be much more severe than the effect of any supposed terrorists themselves!
Better instead to use any such resources on things more beneficial to the common welfare, and to get rid of the extraneous legal authority.