Government spending has only gone up, but public debt has gone down under the Clinton administration. I'd like to see a serious effort to bring spending in line right now, with the Republican Congress, but they haven't done much there.
We have a growing population and an economy that normally experiences moderate inflation. Trying to bring spending down in nominal terms would require vast cutbacks in terms of government services required. Even more vast when you consider that most government spending is simply giving people the social security/medicare/medicaid/unemployment insurance (insurance, not welfare which is like 2%) that they paid for and those aren't going to get cut because people paid for them and expect to receive them.
Suppose that you completely eliminated every last dollar spent on defense over 7 years. That wouldn't bring spending down in absolute terms, it would just level it off.
Suppose that you completely eliminated every last non-defense discretionary dollar over 5 years. That wouldn't bring spending down in absolute terms, again, just leveling it off.
Eliminate them both and you've got us level for 11 years... assuming that society hasn't collapsed into anarchy long before this point.
Because either of these would be simply vast. One would be eliminating the entire damn military, everything, soldiers healthcare and pensions, everything. One would be shutting down basically everything that you think of as "government", post office, NIH, NASA, FBI, FEMA, the federal highway administration, the smithsonian, border control, everything.
While there is a little fat to cut in military procurements and the size of our armed forces (but not enough for what you are talking about without a severe shakeup), we've already spent 15 years cutting the non-defense discretionary spending until there's nothing easy left to cut. Going even a single year with a reduction in net government spending would involve huge sacrifices. Because even just holding spending constant means cutting everything in defense and non-defense discretionary by 10% a year per-capita in real terms.
So if someone tells you that he is going to bring government spending down in real terms, ask him to explain what very substantial government programs is he going to end? Will he completely end welfare, NASA, the national health administration, every cent of foreign aid and all government highway funding? Well all those together would make us break even for about a single year.
Meanwhile the US has something like the 7th lowest tax rate in the world and a system that is basically an overall flat tax when you account for regressive state and local taxation as well as progressive federal federal (which means the poor people in the more regressive states pay more of their total income in taxes then the rich in those states). So increasing revenues with a more progressive system is entirely feasible from an economic standpoint.