There are legitimate reasons to discern between the deficit and those other things. Most law systems are based on a small set of core values which are deliberately made hard to change, i.e. made part of the supreme law.

I believe that the (preventing of) deficit has the characteristics shared by those core values: there is a consensus that it is bad (especially in the long term) and yet there's strong temptation to create it for the short term benefits (buying votes.)