The debt is a worse threat than terror to our country I believe. The debt has the potential to ruin America as we know it. Terrorism will not really end the United States as we know it, although I agree that terrorism has fundamentally changed some aspects of our culture. I think the debt is still worse.
Debt is not a worse threat than terror because debt cannot murder you. You can't be blown up by debt. That said, debt is a much more common threat than terror, and is more relevant to our everyday lives. You are much more likely to have debt than to be a victim of a terrorist attack.
I think that potentially, using debt to destabilize the United States might be a method employed by its enemies. But at the moment and foreseeable future, our collapse has no benefit to those that have the ability to shift the market in such a way. For a country to be so tightly integrated into our economy, they would have to establish long term trade deals, which usually lead to peace between the nations.
Of course to be in debt is a terrible position, but you can survive through it, and not live a life of terror. I know there are a lot of people in debt. The amount of debt in the U.S. Is horrific, however, there has been more terrorism in schools, in public places, and even in your own home.