Huh? Where does he say that?
Why right here:
Madison "was worried about opponents who would think Congress would call up state militias and nationalize them. 'That can't happen,' said Madison," said Breyer,Well then obviously Justice Breyer must take to task the decision in Perpich v. Department 1990 of Defense which re-enforced and ruled constitutional the National Guard Mobilization Act of 1933 and the Montgomery Amendment of 1987 which federalized the NG and then stated that Governors couldn't withhold consent.
So the 'state militia's' (which according to another SCOTUS decision, MD v US 1965 "The National Guard is the modern Militia reserved to the States by Art. I. 8, cl. 15, 16, of the Constitution.") have been permanently nationalized and have been called up near indefinitely but we don't hear a peep about that.
SIH has more. Of Arms and the Law.