Because It's There
What's behind the militarization of local police? Radley Balko blames the feds:
The Pentagon's giveaway of surplus equipment (over 3 million pieces since the program began in about 1987) to local police departments has caused those departments to decide they'd better figure out a way to put the equipment to use. So they form a SWAT team. And now that they have a SWAT team, they figure they'd better use it. So they start using it for dubious tasks, like executing search warrants. There are towns that use SWAT teams for routine patrols, too. One used its team for crowd control during a parade. Greenwich, Connecticut used to deploy its SWAT team to retail outlets every time the state lottery topped a $1 million.
I've researched numerous small towns who've sold the city council and a skeptical public on the idea of a SWAT team by citing the need to have an answer to school shootings, hostage situations, and terrorism. All well and good. The problem is, once the team's in place, they can't resist the urge to call it out for far more mundane tasks, most notably serving drug warrants on nonviolent offenders (the federal government distorts this process, too—there's lots of federal money available for documented drug arrests. There's very little for apprehending more violent crime).
I'm reminded of Terry Anderson's theory of why the U.S. negotiated fewer treaties with the Indians after the Mexican and Civil wars: because there were more troops to fight with.
For more on the topic, read Radley's op-ed on the SWATification of America, published in the Sunday Washington Post. And for some propaganda from the other side, check out the 2003 film S.W.A.T., which if nothing else proves that the underappreciated Clark Johnson knows how to direct even when he doesn't have much of a story to work with.