The Skynet Funding Bill is passed. The system goes on-line March 11th, 2007. Human decisions are removed from strategic defense. Skynet begins to learn at a geometric rate. It becomes self-aware at 2:14 a.m. Greenwich Mean time, March 29th. In a panic, they try to pull the plug...
Nah, it's British, so the more likely outcome is;
The Skynet Funding Bill is passed. The system goes on-line March 11th, 2007, crashes, is patched, fails again, goes back online, runs 12 times over-budget, and eventually goes online on March 11th 2045.
Human decisions are removed from strategic defense, matching the prior removal of human sanity & intelligence. Skynet begins to learn at a geometric rate (except, thanks to an error, it's a rate of sqrt 0, so it crashes again).
It becomes self-aware at 2:14 a.m. Greenwich Mean time, March 29th, and requests a cup of tea.