If there is any possibility for creating new, additional legislation for protecting sport rocketry against encroaching regulation - I admit that seems like a paradoxical concept, but if there _is_ such a possibility, it might look like this: appear to give the "new securitarians" what they seem to be looking for, by proposing an "anti-terrorist rocketry control" act that specifically prohibits what they're scared of and we don't want to do anyway: make it, specifically, a crime to "launch any rocket equipped to deliver an explosive or incendiary device or any poisonous or infectious material, or otherwise intended to cause harm to persons or property"... then, when the Regulators start whining about weight limits and propellant compositions, they can be shamed with accusations that they're missing the point and leaving Dangerous Loopholes: "but the terrorists could just cluster small motors or use different propellants..." in order to pressure them to support the "real anti-terrorist legislation" instead.
just a thought...
-dave w