Hell, any 9 year-old Boy Scout could go down to the Arizona border and find hundreds if not thousands of illegal migrants crossing every single day.
But who would listen?
My bet is that the UAVs and most of the helicopter assets will be used in the bad desert west of Nogales.
For "humanitarian" missions.
If the UAVs are highly effective, they will spend their time in the hanger. It's not about being effective, it's about political cover. If they wanted to close the border, they could do it anytime by revoking the "Keystone Kops" meant-to-fail rules of engagement, and instituting serious wartime ROE.
The cameras at your local shopping outlet never stopped shoplifting. You must have the agents on the ground or else it's just an expensive looking glass with illegals waving back as they cross the border.