Saul makes the point (in a chunk of the article which I resisted the temptation to quote) that natural resources are real and physical, and exist within the boundaries of real national entities.  So that -- as long as national entities control armies and borders -- the transnationals' access to resources is dependent on the consent of nation-states (which is why, though again he doesn't go there, transnational/corporate interests work so hard to install and maintain compliant puppet/comprador elites in countries whose borders include valued resources).  The prospect of genuine democratic government in regions with exploitable resources is anathema to the corporatocracy.

If we take a dystopian view, we may imagine corporations fielding private armies (as DynCorp and Blackwater already do, but so far as renta-mercs in ostensibly national conflicts, not as the shock troops of an explicitly industrial resource grab).  OTOH, some would argue (Butlerians, and I mean Smedley not Samuel) that we've already been there forever -- that the US armed forces have been for at least 3 generations the private army of US corporate interests, sent hither and yon to defend the borders of UFC, ITT, oil barons, and the like.  Is the invasion of Iraq a nationalist war or a corporate war?  Was the occupation of India by the Brits a nationalist/imperialist action or a corporate/commercial action?

The difference between theory and practise in practise ...