I suppose the bright side is that we were underwater during WWII and it got better with each administration from Ike to Carter. Every administration since Carter has spent like drunken sailors save Clinton.
Reagan/GHWB averaged almost 2% per year debt growth to GDP. Clinton averaged 1% per year the other way, then W went hogwild on spending, averaging 4% debt growth to GDP per year (especially bad in 2nd term) and Obama continued that.
In a best case scenario, even in the economy boomed, it's unlikely Obama could bring this ratio back down to 2008 levels. This is going to take decades to get back to Clinton levels, and I doubt we'll ever see debt ratios like Nixon/Carter again.
You can already see the start of a leveling off from the chart. My guess is that deficit growth slows down because it has to, but it'll still be bumping $19-$20 trillion at end of 2015 and the debt ratio will still be more than 100%. I doubt we see a huge drop in debt/GDP ratio until the boomers are through Medicare and dead. So probably another 30 years before the US can even think about getting back below 90%.
e-of-gdp.png