Whatever the merits of zero based budgeting, that is not what is happening in DC, because much of the spending is mandated by laws (and cutting it would be wildly politically unpopular). Most of what we spend is on Medicare, Social Security, Medicaid, veterans benefits, and interest on the national debt. Much of the other stuff is attached to powerful constituencies, like farmers, or is broadly popular (try cutting funding for schools and see how red state parents react when their school loses budget). I'm a libertarian. I'd be fine with zeroing out the budget for the department of education. But the public wouldn't be, and it's important to understand that political reality.
See Tweet