1. What is the Constitution option?
We're talking about the 14th Amendment, Article 4, adopted in 1868. It says,
The validity of the public debt of the United States, authorized by law, including debts incurred for payment of pensions and bounties for services in suppressing insurrection or rebellion, shall not be questioned. But neither the United States nor any state shall assume or pay any debt or obligation incurred in aid of insurrection or rebellion against the United States, or any claim for the loss or emancipation of any slave; but all such debts, obligations and claims shall be held illegal and void.
2. Why it doesn't apply to our present debt crisis:
The Article is part of the 14th Amendment pushed by radical Republicans in the post-Civil War era to extend their political power by ensuring the citizenship and voting rights of Negroes. One might think of the Amendment as the beginning of the Reconstruction era, since it sanctioned the dividing of the South into five military districts. Article 4 ironically disallows Southern, or Confederacy debt (e.g., reimbursement for the loss of slaves, etc.), while allowing for the legitimacy of the Federal debt. The Article became law in 1868 after its ratification by the States. At best, it recognizes the legitimacy of the national debt. The post-war government needed revenue sources after fighting an expensive conflict. It wanted to be paid. The Article doesn't allot the right to increase that debt. I have yet to find any proponents of implementing this Article quoting beyond its first sentence. Reading the Article in its entirety clearly establishes its post-Civil War context and limitations.
3. Why it would be bad policy to invoke Article 4 of the 14th Amendment:
Resorting to this solution would set dangerous precedent, giving future presidents a blank check on spending without Congressional approval. The Constitution is clear on its mandate for a check-and-balance system of the Congressional, Judicial, and Executive branches of government. Besides, we want a solution to our overspending, and not its perpetuation.
In the short run, it would likely incite an impeachment attempt even though it would fail in the Senate, where Democrats hold a slight majority. At the very least, it would add to the fractiousness between the two parties and heat the political temperature still further as we head into an election year.
It's sound policy, whether at the personal or government level, to always weigh the possible consequences of any decision. Decisions are like stones cast into the water. They make ripples.