Stock market? Fed manipulation? Social Security? Medicare/aid? Obamacare? War spending? Trade deficits? Inflationary pressure? What will ultimately be the "last straw"? It's not really what most people think. All of these are parts of a failing system, but I think the "last straw" will ultimately be something less direct. The current POTUS and Congress has been able to rack up massive amounts of debt with little short term consequence due to the current super low interest rates. But when those rates go back to normal levels, the consequences will be massively amplified. Think real estate bubble. If rates spike above historical norms due to inflationary pressure and/or defaults (and compounded defaults from not being able to pay the rising interest payments), the impact will be amplified exponentially. Currently the treasury is paying an average of < 2% on all the national debt. In the 1981 the treasury rates peaked at 20%. Currently about 9% of the total revenues of the Federal Government (including all types of taxes, tariffs and other receivables) on an annual basis go to paying interest on debt. If the rates went to 20% as they did in 1981, just the interest payments would quickly become more than 100% of all revenues. 1981 was bad, but the debt at that time was only about 1.5 x revenues. Today the debt is approaching 7 x revenues.
In personal finance terms, it's the real equivalent of someone with a $50,000 salary, 5 of their own kids plus an adopted Hispanic kid with medical problems and an existing house payment racking up $350,000 in credit card debts at a 2% introductory rate and then having the the rates switch to their "normal" 12-20% rates. The big difference being the consequences of an individual declaring bankruptcy vs an entire country.
So what to do about it? Well, kicking the crooks that got us here out would be a start at least... http://ramblingamericanmind.blogspot.com/2013/11/comprehensive-plan.html