The solution to debt is not more debt. At some point someone is going to have to be grown up about this. It would be nice if they were grown up sooner, so that it hurts less. I'm not holding my breath.
Also, the US makes enough tax income to pay interest on it's current debt. In other words, "default" is not a consequence of refusing to raise the debt limit. Something will have to go unpaid, but it doesn't have to be the USA's debt interest. People are running fast and loose with the meaning of the word "default". Don't let them take you in.
Social security is an unfunded liability, currently funded through a Ponzi scheme, which is just now entering the "not enough new suckers" phase. (No, really, it is. There is no SS "trust fund". I can write checks to myself all day; it doesn't mean I have more money.)
Medicare is a disaster in terms of cost.
The US spends each day double what it takes in in taxes.
The US decided to take what was entirely a private problem (big banks would go bankrupt because they made bad bets on housing) and turn it into a government problem by bailing private entities out that should have gone bankrupt, and then guaranteeing lots of other debt. This actually prolongs the problem and makes it worse.
The Federal housing entities are some of the worst culprits, helping blow the housing bubble, and now pretending they are not bankrupt. They will have to implode and be shut down at some point. Bye bye Fannie and Freddie.
The inmates are running the asylum. It seems the solution to being seriously in debt is to spend more. There is also apparently a magical money multiplier that makes government spending somehow blessed and better than private spending. We have economists making arguments based on very dubious differential equations in which they carefully never specify their boundary conditions. The well known "economists" are more about justifying their political leanings than any actual scholarship.
Public union pensions for federal and state workers are unfunded to the tune of tens of trillions of dollars. These will never be paid out.
All of these chickens will have to come home to roost. Arguing about Democrats or Republicans or Left or Right completely ignores the fact that reality will eventually force a solution.
The current administration will do all of the worst possible things they could do. Not because they are evil, or Democrats, or whatever, but because bureaucracy is about protecting the way things are now. Their universe does not include actions which could fix this problem, because they would change the power balance and the money flows upon which they depend. The Republicans are being forced to pay lip service to the concept of being fiscally responsible by entities such as the Tea Party, but I can't see them doing anything real. They too are bureaucrats, and they too have rice bowls to fill.
If any entity did force some kind of resolution, it will be vilified by all and sundry, because resolution involves the death of a million sacred cows at all levels of this society. There's no upside for a politician in being vilified for doing something that will hurt this much, even if it's the right thing to do.
It would be nice to say that we get to pick whether we try to deal with it now, and maybe have a little control, or later, when it will be completely out of our control. In reality, I can't see that choice having any chance of being presented.
The Financial Crisis never ended. It was just temporarily papered over by insane government spending. Now we just have a bigger can to kick down the road.
A massive failure is coming, whether it be a cascade failure, or death by a thousand cuts. I have no idea when or how. I wish it would happen sooner so I can start concentrating on rebuilding, instead of trying to dodge falling pianos while the world at large tries to pretend we're in a light summer rainstorm.