Basically staging the standard of review for future cases on lower courts.
Underline added--
Take note of that. Its important language. Not difficult to understand either.
Nemo
In the years since [Heller and McDonald], the Courts of Appeals have coalesced around a ?two-step? framework for analyzing Second Amendment challenges that combines history with means-end scrutiny. Today, we decline to adopt that two-part approach. In keeping with Heller, we hold that when the Second Amendment?s plain text covers an individual?s conduct, the Constitution presumptively protects that conduct. To justify its regulation, the government may not simply posit that the regulation promotes an important interest. Rather, the government must demonstrate that the regulation is consistent with this Nation?s historical tradition of firearm regulation. Only if a firearm regulation is consistent with this Nation?s historical tradition may a court conclude that the individual?s conduct falls outside the Second Amendment?s ?unqualified command.?
