The US likes to think of itself as the root of the tree, and maybe it even was for part of the 20th century (the US was central to a lot of manufacturing and design), but those days seem to be over now. As a citizen of the US, I find that scary, but only because I think many people in the US will fight tooth and nail to try to keep being the root.
The world pre-WWI was actually quite globalised[1], more so than most people today would imagine that it was. Yet that wasn't enough to prevent the horrors of WWI trench warfare. I think a similar fallacy exists today - that globalisation will prevent WWIII. Violence and combat has existed for all of human history and there's no reason to think it will ever disappear, sadly. In a few decades anyone that remembers being alive during WWII will be dead and the possibility of WWIII will become stronger, IMO.
Just like the Glass-Steagall act was enacted after the 1929 crash[2], but repealed once the scars of the Great Depression had faded from the public's consciousness, the spectre of the outbreak of WWIII will loom ever larger as those who remember the horror of WWI & WWII pass on, and the lessons learned forgotten.
[1] http://www.americanforeignrelations.com/E-N/Globalization-Fi...
AND Germany...
AND Brazil...
etc...
It's the nature of that particular tech.