I'm pretty sure they're referencing John Hanke, who used to work for the U.S. govt, founded Keyhole through funding from In-Q-Tel (CIA's VC), which ended up spawning Niantic.
It seems they're actively working with the NGA, NSA, DIA, and CIA. It could be just for 3D geo-spatial tech, or it could be for sharing data. It's secret and it doesn't look like conclusive evidence of data sharing has been published. My personal belief is a little bit of both is going on.