I see your point, I suppose criminals could always mill off the serial number but, that would be a federal crime - probably wouldn't stop them though.
It would be a good idea if there weren't flaws but since there are ways around it, it may not be worth the cost.
I think making people go through a gun dealer when they go to sell or purchase a fire-arm might be worth it though, I think having everyone go through a NICS background check is worth it.
Unfortunately that probably would not be enforceable unless there was a fire-arm registration which worked.
It would be a good idea if there weren't flaws but since there are ways around it, it may not be worth the cost.
I think making people go through a gun dealer when they go to sell or purchase a fire-arm might be worth it though, I think having everyone go through a NICS background check is worth it.
Unfortunately that probably would not be enforceable unless there was a fire-arm registration which worked.