If I see something that catches my interest, I will also generally stop to take the time to investigate like you do even if other people think it's a waste of time.
However, when I'm hard at work on a project, that basically goes completely out the window. Some of my co-workers have actually said that I go into a "trance" of sorts. I tune the rest of the world out almost completely, and go into a "machine mode" like you described as I try to work the problem at hand to completion.
It's not terribly unusual for people to even have to raise their voice a bit or physically touch me to snap me out of it.
I honestly have a hard time ever picturing you as an INTJ given how you've described yourself. You seem like too much of a social butterfly, and a lot of your political views (on the military, for instance) are rather decidedly turned towards the "feeling" side of things.