uh.. you didn't really understand what I wrote did you? You don't need to keep interest rates low, in fact you only have some influence over interest rates. As long as your GDP is growing faster than debt (when you have decent employment and so on) then you're fine, and it's not an issue, and you have quite a lot of knobs to turn to keep nominal GDP growing faster than interest on your debt, especially when most of your debt is at a fixed rate for years.
The problem is it never happens that way. You actually have to consider historical context and pretend this isn't the first time we've been through an economic hiccup. Every problem in the last 30 years has been "solved" with spending - the problem is, when the economic ship rights itself, no one wants to do the hard thing and reduce spending or increase taxes. That's why we have a debt that is now 100% of GDP, an increase from about 20% in the pre-Greenspan era. That is a level that has been associated with economic destabilization, and no one seems to care. Our debt ratio is higher than any time except the time immediately surrounding WWII. This is a real problem. Not for the next couple of years, this could be a problem for decades, and probably will if it's not solved.
If you think you have magical knobs to turn to keep GDP growing faster than interest on your debt, you're deludedl. The problem with all your solutions are things like "As long as....". When you build up such an unstable situation, you rely on those things continuing to be true, and when they fail, they fail hard.
other way around. Anyone who thinks now is the time to be worrying about debt is why you've been stuck in a liquidity trap for 4 years when you could have been out of it 3 years ago. Right now *is* the time to borrow more money to get employment going and get jobs created to spur demand to get the economy going. When demand picks back up then you cut those jobs and raise taxes and so on so that you can ride things along while the debt shrinks away.
Sounds lovely. The problem is when it doesn't work, and you end up having jacked up the debt, and your payments on the debt, only to face interest rates that you can't control any more and an unemployment problem that wasn't solved by your spending. In other words, exactly what happened during the "stimulus". Now what do you do?
Here's the thing: the idiots on the fringe on either side are both wrong. Yes, we need to spend money - wisely - in targeted ways to get unemployment down and the tax base up. We also need to do it in a way that isn't going to build a house of cards that will completely destroy the economy with runaway inflation within a decade of the recession ending. Which is why your mindset is dangerous, and that mindset is pervasive in the global economic leadership right now: namely, the notion that we have a lot more control over the global economy than we really do, that we can fix all problems, and that the cure is never worse than the disease. If they were that good at controlling things, we'd never end up with these problems in the first place.
So when you say things that insinuate that our mounting debt poses no long term risk, I have a problem with that. We can't ignore it. No one ever said it's the only problem that should be addressed - a lovely false dichotomy, to be sure - but we certainly can't go back to the Obama stimulus plan (and touted by such luminaries as Krugman) that we just need to spend a lot of money, and it doesn't matter how.
One thing I've found is that, in the long run, economics is simple. And I've also found that people who think they can outwit the basic principles always end up crashing in the end. What I want is to not be in the same boat when it happens.