I am also confused on how this is a bad thing. I have to ask, if this law is a bad idea then what would be a better one?
If we got a court ruling that this prohibition on suppressors was unconstitutional then one might conclude that this ruling/opinion/finding could be reversed by a future ruling/opinion/finding. If we had a constitutional amendment to uphold the right to possess and use suppressors then we could conclude a future amendment could revoke it. What iron clad means exists to ensure the right to keep and bear suppressors could exist?
What we might see is a Tenth Amendment type of law, court opinion, or executive policy that claims even federal restrictions on suppressors do not apply in Iowa. This is not without precedent, states have legalized marijuana possession while federal prohibitions exist. What separates the two?
A marijuana plant is at least something with a scent that is largely unique to it, a drug dog or sniffer device could seek them out. Marijuana is a plant and like all plants they take time to grow, need clean water, light, fertilizers, etc. An oil can suppressor is a piece of metal that can be milled out by a hobby machinist in minutes (perhaps seconds) and can be mass produced at an incredible rate by someone with minimal machining knowledge and less than $1000 in tools. Perhaps I just found my answer, marijuana can be tracked more easily than anything related to firearms.
I think the difference is more subtle. Marijuana is seen as relatively harmless by many in the public and in the political realm. We've seen high school kids getting high on TV, raid the cupboards, and then sleeping it off. Suppressors are something seen used in movies only by bad guys that want to avoid being caught by the police. Policy flows from culture.
