While much of the florid, fashy antics of Immigration and Customs Enforcement, or ICE, has lingered long in the memory, there’s one thing the agency has been doing that’s largely flown under the radar—its efforts to surveil protesters using sophisticated tracking technologies. This represents a realization of warnings that privacy advocates have long expressed: the tools of the war on terror would be turned on Americans by an authoritarian. According to a recent report from Wired, during the unrest in Minne…