It is correct to demand that rich nations like the USA, France, etc. demilitarize borders; accept refugees, whether or not they can prove they are victims of political persecution; protect workers' rights, regardless of immigration status; stop cracking down on illegal immigration; stop the war on crimes (especially drugs & prostitution); etc. At the same time, Marxists have to explain to activists & others why capitalist states will never fully meet such demands.
Does it make sense, however, for Western leftists to demand that China, Vietnam, & other poor nations in Asia, Africa, & Latin America abolish or relax border controls? What do you expect to happen in poor nations (many of which are already war-torn), minus border controls? They won't turn into "realms of inclusion," with or without border controls, to say the least. Are you being nostalgic for the days of "foquismo" a la Che Guevara's Bolivia campaign?
For poor nations to have no control over their borders is likely to mean that they are freely invaded & occupied by imperialists. "No-fly zones" that the USA & the UK have maintained in Iraq are just one of such examples. In less tragic but still problematic cases, lax border controls translate into the growth of the so-called informal economy which cannot be taxed, & insufficient taxation leads to the corruption of civil servants, inadequate social services, etc., which in turn fuels the informal economy.
Generally speaking, no state = no enforceable rights.
The collapse of capitalist states _on the periphery_ is a good thing _if and only if_ socialist revolutionaries are poised to take power & establish soviets. In the absence of Leninist revolutionaries, however, one can only expect Somalia, Congo, etc. -- a bunch of competing factions of armed guys & (direct or indirect) imperial interventions to make things worse. The way the world economy is going, we can expect to see more Somalias in the near future. That's Regress, not Progress.
Yoshie