josh posted on the main TPM page about the Dept of Homeland Security deciding to declare a "Period of Heightened Alert". the ABC News article on the PoHA includes this explanation of the reasons for the heightened alert:

Anti-terror officials in the U.S. cite this summer and fall's lineup of two major political parties' conventions, November's general election and months of transition into a new presidential administration as cause for heightened awareness and action.

gee - the two major party political conventions, plus the summer olympics, plus a presidential election always fall during a four-month period towards the end of a presidential election year. and there is a period of "transition into a new presidential administration" at least every eight years - and certainly the potential for such a transition every four years.

and since the War on Terror (TM) could go on forever (or at least another 100 years!), DHS presumably foresees heightened alerts (with or without terror level color changes) in the summer and fall of every presidential election year for the rest of our lifetimes.

how convenient. a great way to get the populace to vote its fears, rather than its hopes.