We do want the government to protect us from a flood of unskilled peasants willing to work for nothing. Why shouldn't we?
Translation: I'm upset that foreigners can out compete me, and want a socialist government to protect my entitled fat ass from the harsh realities of free market capitalism.
Illegal aliens aren't "the economy." Whenever douche bags don't want to be explicit about not giving a **** about flesh-and-blood Americans, they start talking about an abstraction called "the economy."
You're right. The only economy that matters is the global economy. There is no abstract economy within an arbitrary set of borders, in a modern world of economic interdependence.
People like you are afraid of getting ***** slapped by the rest of the world, but closed borders wont help your stagnant economy.