Obama Stonewalling on Ammo Build-Up

Why is President Obama stonewalling on the government's big ammunition build-up?

"The Department of Homeland Security bought more than 1.6 billion rounds of ammunition over the last year, as well as thousands of armored vehicles."

Do you think he is? What would be the reason?  Is there an ulterior motive behind the government's big grab at gun control? I have heard words like "revolution" and "civil war".  Think it's a possibility?