Buying US debt is an investment. As of now, it is still considered one of the safest investments one can make, and used to balance out more risky investments.
That doesn’t speak to the absolute degree of safety in US debt, but it does to the relative one. Unfortunately, the world we live in is highly dependent on government economic mandates. It isn’t just government issued bonds that are dependent on that, it’s also stocks in private companies, commodities, real estate, even precious metals to some extent (they can be confiscated, for instance).
There’s no escaping that. Within that world, US government mandates are more stable and level headed than most other ones. So, if you are going to make investments, making them directly into US government bonds is about as safe as you can get. If the US government falters, all your other investments will falter too, but that’s not the case the other way around.
P.S. This doesn’t make US debt a GOOD investment. Safe does not equal good. Good is a function of both safety and profit. US debt is safe, but not profitable, and, given the US ability to just inflate the dollar, it will never will be profitable. There are better ways to be relatively safe (through diversity) and also make a profit off of your investments.
If Congress had not acted, the President probably would have gone ahead and ignored it. Since U.S. debt is denominated in dollars, and the U.S. can create dollars, a long-time assumption has been that the U.S. will never have a serious problem paying its debts. If the U.S. debt rises much more, this might create a fear that printing is not pallatable. However, the U.S. is very far from the line that current market-thinking would draw. As evidence, see Japan’s debt-to-GDP ratio, and the calm attitude the market takes toward it. Given this assumption, lots of aspects of the global financial system assume that U.S. debt will definitely be paid – even if in future, inflated dollars. A credible threat of default will ripple through the financial system and cause serious problems. No President is going to let that happen. However, neither can I imagine a President paying interest “to the Chinese”, but stopping Grandma’s social-security check, or the unemployment check of some “hard working American”. A President could simply ignore Congress, and there’s a good chance the SCOTUS will agree.
Just to clarify: there were two issues on the table this month, for Congress: raising the debt ceiling and a budget deal. Raising the debt ceiling was never a serious concern. Sure, Republicans have been using the issue to drum up support for limiting spending, but they’ve raised it before the deadline every single time.
The government shutdown was caused by the absence of a budget deal, and that stalemate wasn’t over whether the US should pay its obligations (to foreign lenders, grandma, or even welfare recipients for that matter), it was over taking on new ones. The President didn’t need to go against Congress, just to meet current obligations: Republicans would’ve voted for whatever legislation is necessary to do that nearly unanimously. They don’t have a problem with doing that.
I understand that you’re talking about the possibility of Congress failing to raise the debt ceiling, but it’s still important to understand the goals of House Republicans who are vocal about the issue: their goals are to limit taking on further obligations, not to default on existing ones. This means that Obama, by circumventing the Congressional power to set the debt ceiling, would accomplish nothing to further his own agenda, and would in fact be furthering the Republican agenda (honor current obligations, take on no new ones). Obama’s agenda is to take on new obligations. He can pay current obligations without Congress, but he can’t take on new ones. All ignoring Congress on the debt ceiling would do is turn it and public opinion against him, and make it less likely that he’ll get his way on the issue he’s really concerned about. These types of crisis and deadlines benefit his agenda, because they force Republicans to agree to new spending they wouldn’t normally agree to.
On the other hand, a fiscally conservative President faced with a liberal Congress, would have the upper hand by acting the way you describe. In that scenario, Congress would presumably be using the debt ceiling to extort concessions towards greater spending, which the President can circumvent.