You forgot Food Stamps and Unemployment ($420 billion) and interest on the debt ($229 billion). You could cut every single penny of non-defense, non-security discretionary spending and you would still be $500 billion short of the $1 trillion in cuts per year you would need to meet the spending reduction goals.
I didn’t forget them. They were part of the $1.5T. Foodstamps are only $75B so I’m not sure where you got $345B for Unemployment to make up your $420B figure. You may have included Medicaid or other welfare costs in your $420B figure. Regardless, getting all spending under $3T when SS/M + Military already accounts for $2.1T seems pretty tough. That is the bottom line, actual spending must be under $3T in the first year to achieve $10.5T total cuts in ten years.