In many movies (Transformers, Independence Day, etc) I see a group of men do something amazing like call in an air strike or mobilize some kind of defense using something as simple as a cell phone. Or in some cases morse code. Is such a thing possible? If i needed air support in Iraq and all i had was a cell phone and credit card could i really get the support i need? How long would it take? Would the call be soemthing like you would call you Recrutier>Your Home US Base>Base of Operations>Pentagon>Revevant carrier group. And could you just keep transerfing a cell call to where you needed it to go like the pilots or wing commander?
Well, a unit in Grenada managed to call in air-support by dialing the Pentagon on a land-line in a local building. I’m sure there were authentication protocols involved, but the capability exists.
When I worked the overnight shift on the 24-hour-desk at one of my assignments, I was given a Big Damn Binder with telephone codes. If a call came in on one of the phones in particular, I was to answer it to the exclusion of anything other than the building burning down, open the Big Damn Binder, and connect the caller to anyone they asked for. It never rang, but I was ready.
I still have no idea who was going to call or why – I was just following orders. 
When the general wants to make damn sure he gets his pizza in 30 minutes . . .
One of the best phone calls I ever made was to my father: I was on an Iridium satellite phone on top of a sandbagged bunker in Afghanistan, and connected through the front office of his factory to a landline extension phone in the back of the warehouse.
Between this, SINGCARS radios, the Blackberries/Treos my bosses carry every day, webmail availability, FM/VHF/UHF ‘Bricks’, our SIPRNet, and the sometimes locally-contracted cellphones, yeah, we can pretty much get our message across to whomever.
Tripler
Yeah, we got ways to order Billdo’s pizza for my General.
Back in the early 1980s I was in the middle of a jungle in South America. I pulled my handy satcom terminal ($250K, 3ft x 3 ft x 2 ft) out of my jeep, set up the collapsible pizza-sized antenna, hooked up a field phone for audio & proceeded to dial the internal DOD number for the base nearest my parent’s house. When the operator answered I asked for a local out-dial connection, dialed again & my Mom was amazed to hear my voice. That was 25 years ago next month. Technology has improved a bit since then.
With a cell phone you need to know who to call. If you have that, or can find somebody to help you get it, you’re golden. Once you get a command post on the horn, authenticating who you are, where you’re at, and what you need will be a challenge, but that’s a bureaucratic challenge, not a technical one.