The real surprise to me is that it has taken them this long to put something in writing about this.
The root cause of the issue goes back decades to the language of the laws themselves. And the underlying concept goes back to the middle ages, or perhaps earlier.
More specific to this matter, the law says that they get to determine what a part is intended to be, and only that matters. Whether or not said part is actually used in an illegal manner doesn't matter. Whether or not said part will actually WORK doesn't matter. It's deemed illegal because they say its intended for illegal use.
This is yet another case of being guilty until proven innocent (if you even can be) just because the law was written to allow it, or even encourage it.
Its also an example of the govt assuming intent in general and punishing people in specifics not because they should, but because they can.
And applying that concept unevenly and unfairly.
Nearly every household in the country has things in it that COULD be made into a bomb. Every car with airbags has a detonator in it. You can make deadly toxins from dead animals. You can kill someone with anything, including your own body. Etc.,etc.,etc.
Generally speaking, its not criminal to have these things until you actually try to do something illegal with them.
But not gun parts, oh no. Make no mistake silencer parts are treated as gun parts, they are covered under gun laws.
Constructive possession (for one example), and determining you are guilty of some legal violation without actually attempting or doing a criminal act, is a long standing, and I feel flawed tradition in our system.
Sure, I'm aware of people intentionally skirting (or breaking) the law for profit (actual or perceived). But lumping everyone together doesn't seem right to me, common though it is.
There is an old joke that has some very valid points in it, about a ranch hand who stops into the saloon for a drink while he has fence post pliers in his back pocket.
The Sherriff comes in, sees the wire cutters, and arrests the guy for cattle rustling. Says, "Sorry Slim, I gotta take you in, fences been cut, cattle been rustled, and you got the tool for it in your back pocket..."
Slim replies, "ok Sherriff, I'll go peaceable, but I didn't do it."
"Don't matter, Slim you got the tools for it right there!"
"Well, in that case, you better arrest me for rape as well, cause I dang sure got the tools for that, too!!"
I hope you can see my point.