The lack of enforcing immigration laws on invading hordes is #1 on that list.
Unlike many apparently, I think the ideas and values of freedom are stronger than ideas of tyranny and servitude. I don't think you have to be so afraid of people - the "multitudes in the valley of [in]decision" will vote for their self interest in liberty if, like Reagan said, they are clearly shown their worth, value, and happiness as free individuals.
I'm in favor of border security as I've said from the start. I've also said that it seems to make sense to deport illegals in prison (at least the convicted ones) and some other things that can be done. Deporting 30 million sounds ludicrous and dangerous because it would be another opportunity for Obama to install his much desired police state to make it happen. But let's call what we are saying what it is. And the issue of sharing entitlements is a socialist-based argument.