Can anyone explain what TFR's are supposed to do?

I haven't figured out why TFR's exist. How are they supposed to
protect the President and/or whatever else?

Does the Secret Service and the FAA really think that just having a
"no flight activity" within an imaginary circle sixty miles across
will really stop a determined assailant?

Besides, light airplanes just don't have the hitting power to cause
much of a problem for anything but a "soft" target, and any soft
target would be so small as to be an immensely hard target to hit, not
to mention how difficult it would be to be at the right place and time
to actually have a shot at hitting it while it's in the open.

I mean come'on, once the president's airplane is on the ground, he's
off and rolling on a schedule that has him moving constantly. Talk
about a moving target! And then when he stops, it's often inside a
big building.

Those times he might be scheduled for an outdoor address, I can see
the Secret Service getting a bit uptight about that and not wanting
stray airplanes around at that point, but how often does that happen?

Are the airliners prevented from flying within the TFR? If not, can
someone explain why not? It wasn't a lightplane that caused the
collaps of the WTC.

Is the TFR anything but a panacea for the Secret Service? Something
they can point to as proof that they take their job seriously?

Sort of reminds me of that old joke about a guy walking down the
street who spots another guy jumping up and down and waving a bag
above his head. The first guy stops and asks whats going on. The
second guy says he's scaring elephants away.

"There aren't any elephants around here." The first guy says.

"Pretty effective isn't it?" The second guy responds.

Corky Scott