By JEB BUSH AND KEN MEHLMAN We support the immigration reform compromise worked out in the Senate for a few simple reasons. It strengthens our national defense. It makes our economy more competitive and flexible. It enhances the rule of law and promotes national unity. And it also does these things in a fair, practical way. The bill provides real border security for the first time, protecting us against the entry of terrorists and stemming the flow of illegal drugs. The temporary worker program will reduce the number of people trying to sneak past the border patrol, allowing law enforcement...