Denver, Colo. – There’s a stretch of Broadway that’s called Broadsterdam because of its medical-marijuana dispensaries. Just a block over, flanking Acoma and Bannock Streets, is a warehouse district. It’s not hard to guess which of the squat drab buildings are grow-ops (marijuana-growing operations) — they’re the ones wound in razor or barbed wire, with protruding cameras, barred windows, and extra air-conditioner units (the lights needed to grow plants make it hot in the warehouses, but the plants need cooler temperatures). Sometimes when you drive by, you can smell weed wafting in the breeze. And deep inside at least a few …