This post notwithstanding, getting the District of Columbia a fairer shake in its self-governance and Congressional representation isn't really one of my causes. However, I'm sufficiently familiar with Washingtonians' complaints that Will Baude's comparison of the House's repeal of the D.C. gun ban to the Gun Free School Zones Act of 1990, for the purpose of saying "it is rather odd that the Times suddenly rediscovers federalism when it is a federal enclave at issue," struck me as somewhat facile.
When Congress passes legislation applicable to the 50 states, the members are acting on behalf of the people who have elected them, who are the same people for whom the law will be enforced. When Congress makes rules for the District of Columbia, no DC voter has put a Congressman into office; their only input is through a non-voting delegate. Therefore there is a degree of democratic accountability in something like the GFSZ Act that is absent from the DC gun ban repeal. Had the GFSZ been opposed strongly by the majority of people who would have to live under it, it would not have passed (nor would the Lopez-bypassing Act of 1996). The gun ban repeal may be opposed by the majority of Washingtonians, but the House needn't give a damn.
The Constitution gives Congress the power "to exercise exclusive legislation in all cases whatsoever" over the District, but the Times was not making a Constitutional argument. It was making an argument about political fairness, and for a city to be governed by a body in which it has no power whatsoever does seem rather unfair, and also likely to be abused. Lobbyists for an industry that may be contrary to the interests of the people will have more sway than the people themselves. In light of DC's problems, this reminds me of when some libertarians went to Harlem to pass out toy guns before New York City banned their sale, an incident immortalized by the Daily Show in "Guns for Tots."