First, the pilot in question still gets to have a hearing. A private pilot certificate is one of the few remaining licenses that are actually good for life. My guess is that a suspension is likely, but I doubt he loses his ticket. That happens, but it is very rare. Second, a "student pilot with only 30 hours" is only 10 hours away from the minimum for a check ride and almost certainly post-solo endorsement (check rides are usually taken with 45-50 total hours and solos 15-25 hours, but there are exceptions).
Finally, unless the law has changed, only the President of the US can order the downing of a civilian aircraft in US airspace (that's why Clinton had to give the okay to shoot down golfer Payne Stewart's aircraft if it looked like the aircraft was going down over a largely populated area. It didn't, it ran out of fuel and crashed in the Dakotas). Since the toddler was out on a bike ride and didn't even know of the incident until well after the hysteria had dissipated, those in charge of the "missles" would have almost certainly got a hold of the pResident if they had thought there was the slightest chance they'd need to down a Cessna 150. BTW, another popular myth supported by the uninformed press is that the old fart was an instructor - he isn't.