The entire world's economy, as well as many countries political configurations, rely on the United States existing. I doubt it's going anywhere, but hopefully reform might actually happen this time.
>> I feel the same way a lot recently and I would love for someone to tell me why I'm wrong.
> Because every other country in the world has a vested interest in keeping the USD stable as a currency, which would mean that they'd help keep the country up if needed
You're answering the wrong question. The American republic isn't primarily an economic system, it's a political and social one. It can become completely fucked in so many ways without disrupting the currency too badly too quickly.
I know it will be little consolation to me to have the currency remain stable while things descend into pseudo-democratic authoritarianism.