While immigrant baggage screeners stand to lose their jobs because of a post-9/11 federal law that requires all screeners to be U.$. citizens hundreds of migrant workers are being killed trying to cross the border from Mexico. These attacks on immigrants are part of a larger system of closed borders in the united states that keeps profits and wages high for Amerikans at the expense of the majority of the world's people. The border imposes artificial barriers on families, communities, and nations. The border also prevents the development of a real "free market" in labor power. The internationalist section of the Amerikan bourgeoisie complains about barriers to the free movement of capital, but you rarely hear them complain about barriers to the free movement of labor (i.e. people). This is because they -- and the privilege enjoyed by oppressor nations generally -- depend on the depressed wages in Third World countries.
The brutal super- exploitation of billions of toilers in the Third World ensures not only the imperialists profits, but the high standard of living for hundreds of millions living in oppressor countries. It's no mystery why workers in the Third World earn an average of $0.48 an hour, while u.$. workers earn $16.40: Billions of toilers in the Third World live under death-squad governments, which use force to set wage rates and attack union organizers. Death-squad governments supported by the Amerikan imperialists, we should add. Those regimes which do not use military force are competing against those which do, and, unless the leaders mobilize their people for people's war against imperialism, the threat of imperialist invasion remains.
In this context, the border is a tool to keep the vast majority of workers in a situation of most brutal exploitation. Even those undocumented immigrants who do manage to get into the united $tates face brutal exploitation in sweatshops; their undocumented status is used as a lever to drive down their wages. And as we see with the airport screeners, documented workers also face tenuous conditions when Amerikan national chauvinism is rallied into an attack on immigrants and civil rights. Lifting restrictions on immigration into the united $tates would objectively benefit the international proletariat. Workers will not have to risk their lives just to look for work in the united $tates. If a really free labor market develops in the capitalist world, the world-wide average wage will rise, and reforms like an international minimum wage and an international labor-rights guarantee will be easier to push through.