I spent a few days in Missouri last week, giving a talk and hanging out with local campus activists. They’ve got a fascinating senate race in Missouri this year, between Todd “legitimate rape” Akin and embattled incumbent Claire McCaskill.

We talked a bit about the race while I was in town, my hosts and I, and so when I stumbled across a lifestream of the campaign’s first debate yesterday morning, I watched a bit of it. As it turned out, one of the first questions was on the post office.

The mail is one of a relatively short list of government services that are explicitly mandated in the constitution, but both Akin and libertarian challenger Jonathan Dine took aim at the USPS, arguing that its current financial setup is unsustainable. (Akin argued that postal rates need to go way up and Dine said he’d be happy to see the end of Saturday delivery and the closing of a bunch of rural post offices.)

Only McCaskill was willing to stand up for the mail, and to say that the current “crisis” in the postal service is a fiction. Here’s the deal:

Until 1970, the Post Office was a regular government agency, funded both through paid services and government appropriations. But Congress began the process of phasing out government support that year, and by the late ’80s federal funding for the mail had all but disappeared. In 2006 Congress went even further, passing a law that mandated that USPS — alone among all federal agencies — completely pre-fund all its retirement benefits. At a cost of billions, and with no help from the taxpayer, the postal service was required to set aside funding for the pensions of postal workers who haven’t even been born yet.

This was a dumb idea in 2006, but it became catastrophic after the financial collapse of 2008, as declines in postal revenue shattered the assumptions on which it had been based. In the last four years, the USPS has run up a deficit of some $20 billion, entirely as a result of this wrongheaded law. Repeal it tomorrow, and the financial prognosis for the USPS is transformed overnight.

Now, the politics of the mail are complex. The 2006 law arose out of previous federal budget shell-games, and there are corporate pressures on USPS policy from a huge number of sectors of the capitalist economy — advertisers, publishers, private delivery companies, even insurers, convenience stores, and winemakers. Postal policy is a mess in a lot of ways, and not all of those pushing to weaken USPS have been Republicans.

But here’s the thing: The mail is the mail. It’s an unsexy but essential component of the government safety net. It’s a public service we need, one that’s used most by folks with the fewest resources — the elderly, the poor, people with disabilities, people with limited internet access.

If you screw with the mail, you’re screwing with people in need. You’re screwing with the common good.

On that stage in Columbia, Missouri yesterday, only one of the three candidates was willing to stand up for the mail, and it’s no accident that it was the Democrat.

Claire McCaskill is no leftist. She’s not even particularly liberal. Her ads boast that she stands at the exact center of the Senate as its “most moderate Senator.” But she’s liberal enough to believe that the postal service is worth protecting, and her opponent isn’t.

And it’s stuff like that which keeps me voting for Democrats, in spite of the drones and Manning and everything else.

Because until the revolution comes, I want six-day delivery.