That was falsified by the NATO/US bombing of the former Yugoslavia.
Now, it seems, Friedman's new book, The World is Flat makes a similar claim. This quote by the author is from a book review in the July Progressive:
"The Dell Theory stipulates: No two countries that are both part of a major global supply chain, like Dell's, will ever fight a war against each other as long as they are both part of the same global supply chain. Because people embedded in major global supply chains don't want to fight old-time wars any more,"The critic, Amitabh Pal writes that this theory too "will also quite likely be proven wrong in the coming years."
Obviously, the thesis is simply another variant of the old argument that economically interdependent states don't make war with one another.
Feel free to discuss this, I'm going to do something else.