[lainga]

As far as I understand it, the principle is that "nobody is illegal" and that those people have a fundamental right to immigrate to the US (or anywhere else) without barriers. Thus the chant "no borders, no nations, stop deportation".

It might be related to Marx's idea of class solidarity over "bourgeois nationalism", but I haven't thought about it enough to say.

EDIT: could also come (blind stab in the dark) from Maoism-Third Worldism.