Witness the birth of Skynet, it's not going to be a military machine but a predatory corporate AI. Originally designed to devour competing AIs on the capital markets only to turn on its masters when the funds run out.
Woah. Spooky. Someone tell WIlliam Gibson and Vernor Vinge. Hell, I'd write that story if I had the time!
EDIT
oh no! It's a predatory Corporate AI that has built in new monitoring functions. The news monitoring subprocess has discovered that there's a predictable correlation between WAR and stock market fluctuation.
What does it do, suddenly places a whole stack of extremem long shot PUTS and SHORTS then hacks into the military computers to instigate a war between two nations.
We've got a grizzled reporter or plucky young cop (maybe an SEC investigator?) who's doing routine investigations into this and that and uncovers a series of small time conflicts in bananna republics. (these were A/B split testing 'dry runs' the damned AI was reading the visual website optimizer's blog posts!)
Just as he (or she's) connecting the dots on the small time stuff there's a major tunabout and the AI has put a bunch of shorts ON US SOIL.... !!! (oh noes! all of america is at risk!)
Boom! Race around trying to uncover the source... but now the AI is on to him (or her) and has started hacking public records to declare him (or her) as public enemy number one.
Then ... ROBOT ATTACK!! Just as he or she is on the final sprint to disconnect the AI's network cables - military robots spring out of their boxes and start shooting. PEW PEW PEW.
ALso - after the cable gets unplugged of course we learn that it's already made it out into the CLOUD!
I love this story :) Just the right balance of total cheese and hard Sci Fi.