Mr President, move this line

A recent Federal law allows police officers to carry concealed across State borders, even in States that have no concealed carry, even for retired officers.

I generally favor this kind of law, in spite of the separation of civilians into LEOs and non-LEOs, for one reason: it's a step towards rearmament of everyone. I'm a creeping incrementalist. The undecided see that cops and retired cops pose no threat. Next year, they'll see that interstate permit holders are no threat. The year after, they'll see that concealed carriers without permits are no threat. The year after that, maybe we can carry sharp objects on commercial aircraft again.

The people who conceived, drafted, and pushed this bill through appear to have sound Federalist instincts. They recognized that the law would need a Federal nexus, something in addition to the Privileges and Immunities clause. So they added a line that this law requires that the "firearm ... has been ... in interstate commerce" to apply.

Unless you make your own, almost from ore upward, it would be hard to conceive of a firearm that has not been in interstate commerce. The Institute for Justice includes just such targets on its hit list of Supreme Court cases it wants to reverse, such as wheat grown for consumption by the farmer rather than for sale. IJ has no particular pro- or anti-gun position per se, but RKBA folks should see common cause with them.

I would argue that the very moment a firearm is stamped with a serial number by a Federally licensed manufacturer, it enters interstate commerce, even if in intent only. No doubt a resourceful Federal prosecutor, if he's grasping at straws for a conviction, will make the same argument. Some have anticipated this argument and seek to counter it before it happens, and my hat is off to them.

I make this argument not to ruin a Federalist's day, nor to trash my own chance at building my own 1911 in the near future, nor the better to define where that line between private consumption and interstate commerce lies, but to move that line.

Where's my CRC handbook?

Can a transition metal have more than one peroxide, just as it can have more than one oxide?

Seems to me that it could. In that case, I presume that the peroxide should be treated as a radical, a covalently bonded whole that enters ionic bonds with metals. The peroxide radical simply contains two oxygens, covalently bonded together, in place of one, but bearing the same ionic charge as the oxide, all other things kept equal. Lead II oxide is PbO, so lead II peroxide would be PbO₂.

But then would lead IV peroxide have two peroxide ions---would it be PbO₄?

OK, then you understand my frustration with this question: given that iron III oxide is Fe₂O₃, would iron III peroxide be Fe₂O₆, or even Fe₂(O₂)₃?