Timing and side channel attacks

How would you know the US pentagon is planning an attack on Iraq? One possible plan is to infiltrate the pentagon using spies, flipping traitors etc. But this sounds like lots of work and it is a dangerous work. That is the direct approach. Another possible plan is to ask the pizza delivery guys in the area. People planning an attack probably adds up to lots of people urgently trying to meet deadlines, staying late in the office and ordering pizza. So the pizza delivery guys know about a pending attack! The pizza delivery guys do not know the nature of the attack but they know “something is up” in the pentagon because for a few days people are staying late at the office and ordering pizza at irregular hours. The pizza approach is the side-channel attack. This attack on the pentagon is not a direct channel attack. No spies were used. No attack on the pentagon defences. It is a side channel attack. Attack on the side effects of planning something. The people who plan need to work extra time and they also need to eat.