Another take is that the Constitution establishes Congress, the Presidency and the Courts, so if the elitists in the District of Criminals don’t deign to feel constrained by the Constitution, then they are repudiating the very document that created their cushy, worthless jobs in the first place.
If they really want to disregard the Constitution, they have already declared themselves null and void, and of no authority, nor due any respect. It’s not a good idea to ignore the very document that created your job.
However, nobody, anywhere, ever posited that politicians are capable of very deep thought. Is this REALLY where they want to go?????
Strictly speaking, under the USC, it's Congress that shall make no law infringing the right to keep and bear arms. The States are authorized under the USC to be as stupid and suicidal as they want—and they are free to lose population to the other States as a result. They're also free to establish a State religion. Etc., etc.
The District is another matter, since it's Federal property. Judges like this clown don't want to face the full implications of all this—since it undercuts 99 percent of the authority the Supremes have been arrogating to themselves for the past 90 years—but we must, because it's what our founding doc says, and it's what works.