They are making an issue of putting a "military weapon" into civilian hands so as to do an end run around the
Protection of Lawful Commerce in Arms Act.
This act was passed to protect innocent arms manufacturers and dealers when firearms are used in crimes.
Under the complaint, their legal theory is that an "military assault weapon" like a Bushmaster M4 / AR15 should not be made available to a civilian.
It's possible that they jurisdiction shopped to get a sympathetic judge in order to ultimately challenge the law and render it ineffective.
The same legal theory could apply to our Lugers, and impact collectors and dealers since there are no current manufacturers.
This is one of a pattern of actions used to weaken Second Amendment protections in our society and culture.
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Igitur si vis pacem, para bellum -
- Therefore if you want peace, prepare for war.