Somehow White House Down was even stupider.
They use an ICBM to shoot down an aircraft. And not by detonating the warhead, it physically crashes into an aircraft to destroy it.
Well 4-5 min is not a long time unless those jets are sitting on the flightline with pilots in them and engines running. According to a couple online sources an f-16 should be ready to fly in 5 min from the pilot hitting the cockpit. f-22’s supposedly have a more “automated” startup procedure that runs quicker, but probably not much.
15 min for ground personnel, ambulances dont arrive much quicker and they are pretty much standing by waiting for a call any minute.
Then add the time it takes to add ordnance to the aircraft. Unless the aircraft is already sitting in the hanger with live ordnance attached, which involves its own set of problems.
To answer the OP somewhat, I am guessing besides the answer that smithsb posted, there are a few toys we aren’t being told about to prevent airborne threats. Of course, Frank Corder may have slammed his Cessna 150 into the lawn of the White House without help from the Secret Service. Re: C-130s, AIUI they aren’t allowed to operate in daylight, for the MANPADS reason smithsb wrote. Probably different survivability if they aren’t currently in a pylon turn when they take the missile strike though.
Oh I know what a stinger is, used to be “qualified” on the BFV Linebacker, posted without proper follow through on the thought.:smack:
I recall hearing a report on 9/11 of a missile battery being spotted popping out of the White House lawn. Watched all day and never heard another word about. I know I didn’t imagine it because I searched for more information on this immediately afterward and sporadically over the years. Either it was a mis-report of something else happening or someone was cut off from talking about. I suspect the first one but the conspiracy theorist in me wants to believe the second scenario. 
I do believe that now there is a missile defense system for the White House, so googling for information now is biased towards that.
Where is Wesley Snipes when you need him?
Your memory may be faulty. Perhaps someone mentioned something like a missile battery protecting the White House, you filled in some extraneous untrue details, and then time did its work to solidify the misremembered report in your head.
It’s also possible they were wrong. Real-time reporting is often very shoddy. At least one news station that I recall reported bombs at the Capitol building. Didn’t happen.
The security at the White House (and other places) is mostly based on what has happened historically in the past. And that is “lone nut cases” trying to get in. One person. So you will find they are best equipped to handle that type of thing.
Note that nut cases typically are not successful people dripping in money. So they would typically not posess a helicopter or C-130!
Businesses handle security in the same manner. It is history which dictates various levels of security per insurance company dictates. Therefore you might find a “beer warehouse” to have very sophisticated top of the line security systems - much better than a bank. And that is because they have had more break-ins in the past [than banks].
I don’t think it’s a false memory because I clearly remember thinking when I heard it “that’s odd and interesting” and kept waiting for a follow up news report that day as they tracked the plane that crashed in Pennsylvania. But then again that day was choke full of news and misreported stories. So much real news that following up speculative sightings didn’t merit a followup so I wrote it off as such.
You would think that the lawn would have shown some indication of an opening into the ground anyway.