I wish you had some source for that assertion. All reliable sources I have seen most certainly do not agree with that position. This is not like some small business that can just write the checks as they come due, and then not mail the checks for a week or so until some money comes in.
But beyond that, if your position were actually true then that'd mean that more money is coming in than is going out, and therefore, no debt ceiling problem anyway. We are all agreed that that is just not true.
Some source for which assertion? That debt-to-GDP is what the issue is here? Sean Egan said it himself in the video I linked in the OP, and he's the one who makes the ratings determinations for Egan-Jones. QED.
Or that missing intergovernmental holdings debt payments matters? It doesn't, though. The Treasury's debt to SS is not like the Treasury debt sold on the market. In fact, it's not marketable at all: the SS trustees cannot sell the debt the Treasury owes them; that's why they're commonly called "IOUs". If it's non-marketable, it has no potential to contaminate the sovereign credit market even if repudiated: it's simply money the right pocket owes the left pocket.
Or that we have enough money coming in to make debt service payments? That's just basic math. We take in just over $2 trillion in tax revenue annually. Our annual debt service is around $300 to $400 billion. Therefore, our existing tax revenue is sufficient to service our debt. Anyone who says otherwise is lying.
So if I just make the interest payments on my mortgage, nothing will happen but good things? First, the bond market will tank, this is what happens when our credit rating is lowered. To sell our bonds, buyers will demand higher returns. We must sell bonds to service our debt so the national debt will increase exponentially until it eats up the savings we might possibly pass in cuts and new revenues. at the same time, banks will have to raise their interest rates as money supply dwindles, small cap business that need short term loans to pay cyclical needs like payroll and inventory will no longer be able to afford them and layoffs and business failures will rapidly occur. Large cap business will lose demand after this and have the same delayed fate. All this will take out trillions from the business economy and throw us into a recession within a month and raise the unemployment to historic highs. The most likely scenario? Obama will find a way to unilaterally raise the debt ceiling, or congress will give him the power in some halfassed way. This will save the economy but enable the GOP to point at Obama as the one who raised the ceiling and blame him for any economic failures in the future. Truth is, the GOP doesn't have the huevos to tackle the crisis they made themselves.
If you make the minimum monthly payments on your mortgage, you will eventually pay down your mortgage. That's what we're talking about here. That's what's been going on for the last two months. That's why the national debt has decreased by a few billion since we hit the debt ceiling.
I've been making minimum payments on my student loans for the last nine months and my debt load has decreased about $2,500 (despite an average interest rate of like 8.5%). Not a lot, to be sure, but the rate of amortization will accelerate as my debt load decreases.
And there's no reason we cannot make those debt service payments. Our tax revenue exceeds those minimum payments by at least 5 times. If we default, it will happen solely because Treasury elected not to make those payments.
Egan-Jones has made clear that our credit rating will be lowered not as a result of our failure to raise the debt ceiling but as a result of our failure to get our debt-to-GDP ration under control. S&P has also said that anything less than $4 trillion in cuts over 10 years will lead to a downgrade. Neither of them care about the debt ceiling, so long as debt service is paid.
For the record, there is no way to "save the economy" here. It's boned, and the only thing that's sustaining it has been unprecedented levels of debt accrual. If we balance the budget today we immediately revert to conditions of economic depression, whether we do it by raising taxes or cutting spending. And if the bond market revolts, we wind up not only with a balanced budget anyway but a worthless dollar on top of that, so we ought to get our fiscal house in order now while the pain is still manageable.