Paranoia strikes deep
The same kind of rumors were going around during the death throes of the Nixon Administration. Didn't happen. Don't see a realistic chance of it happening this time, either.
Think about it: Any event serious enough to make general martial law throughout the entire country even thinkable, let alone necessary, is too big for a real terrorist cell to pull off.
As to the idea of it being "staged" by the Stooges In Chief... I have no respect for them whatsoever, but I don't believe they're genuinely evil.