It is not emotional to say that terrorist groups can profit from creating flash crashes.

That is a very bad thing. The "penalty" to trading is lower liquidity. Before there was HFT there was trading.

Co-location, front running, and now linking terrorism events to flash crash trade positions are risks that you and all other HFT advocates have not adequately addressed. The easiest hedge is to build in limits with regulations and transaction taxes.

HFT is not complicated. What about HFT do you feel is opaque or not understandable by the industry? It isn't as difficult an issue to manage as those who profit from postponement of regulation would have it seem.