What do you mean by this?
If your "hot" referred to speed of delivery than satellite transmission would be the way to go.
If your "hot" referred to the informations sensitivity, satellite transmission can handle
any classification level or compartmentalization once it's encrypted properly.
NEVER, EVER, EVER TRUST Communications lines or encryption unless absolutely necessary! The MOST secure way to keep something secret is to tell NO ONE. The second, only face to face in a situation where you can not be overheard.
For whatever reason, the administration is keeping all revalations regarding WMD's in Iraq as don't ask, don't tell!! I can't understand it, but, if that's the way the game is played, you don't risk ANY leak you can reasonably avoid.
Modern Computer systems can break almost ANY encryption given time and resources. If you have [even a part of] the key it's easier.
Before anyone says, well we trust ...., please ask yourself one question - how many government officials [military & civilian] might have access to the encryption key of the day - AND - if even ONE of them were a rat - what would this mean for national security when dealing with the "super secret"?