The Dell theory of conflict prevention, as Friedman discusses in Chapter 12, is the idea that the world is so economically interconnected that out and out war between major powers is becoming more and more unlikely. Friedman points out that various countries need each other economically and are therefore unlikely to fight one another.
This dynamic is made possible by globalization. Because of globalization, you have many different countries working together within the same supply chain, as Friedman discusses in the long anecdote about his Dell notebook computer at the start of the chapter. Globalization has created all of the economic ties between countries that Friedman thinks will prevent war.
So, globalization relates to the Dell theory by creating the interconnections that the theory says will make major conflicts less likely.