I would think DHS is more worried about
(any) money -> mt gox -> bitcoin -> groups not aligned to DHS interests (any) money -> mt gox -> bitcoin -> groups not aligned to DHS interestsAnd there is always the Tor network for anonymity.
But good luck trying to get the value out that you put in. Dollars and Euros are relatively stable compared to bitcoin. There is a much higher guarantee that you're going to get the same value out that you put in with Dollars or Euros compared to bitcoin. Bitcoin looks like a great investment until you actually try to turn it back into dollars or euros.