Possible, but more likely that left wing rhetoric will lead to another unabomber.
Or that an increasing drumbeat of propaganda will culminate in the American equivalent of the Reichstag fire. Or even in the "assassination" of a secondary Democrat official -- creating a "martyr for the cause".
There are people on the left who would do the deed (think ACORN) and people in the White House who would give the order (think Emanuel/Axelrod).
These people aren't going to let the Tea Parties interfere with their plans.
It's not over...