The Obama Administration has as of yet not been willing to disclose the rationale for purchasing, maintaining and training with the use of weapons of war with the Department of Homeland Security.
There is no reason why a department that has absolutley no war making authority in the United States, should have reason or motivation to use 1.6 billion rounds of ammo (of which a portion is hollow point ammo that is against Hague Convention rules) or the 2717 MaxxPro MRAP (Mine Resistant Ambush Protected) APC vehicles that have been purchased.
These are clearly weapons of war and should therefore be placed under the Department of Defense, the ONLY department that has war making authority in the United States.