[rmnunez]

I suspect if you had these dishes mounted atop tall flagpoles along the fortified wall they plan to build across the desert. Perhaps the dishes could swivel so you could aim them and be enhanced with cameras, but if an individual approached one of these things armed with the proverbial slingshot, perhaps he could render it useless and even the united statians couldn't get away with frying Mexicans in Mexico. They'd have to set them back 500 metres from the border and then they'd need to be swift and powerful to be effective (I'd expect a burning undocumented would move pretty fast).