They have found their punishment in their success: laws overturned; tribunals subverted; industry without vigor; commerce expiring; the revenue unpaid, yet the people impoverished; a church pillaged, and a state not relieved; civil and military anarchy made the constitution of the kingdom; everything human and divine sacrificed to the idol of public credit, and national bankruptcy the consequence; and, to crown all, the paper securities of new, precarious, tottering power, the discredited paper securities of impoverished fraud and beggared rapine, held out as a currency for the support of an empire in lieu of the two great recognized species [i.e. gold and silver] that represent the lasting, conventional credit of mankind, which disappeared and hid themselves in the earth from whence they came, when the principle of property, whose creatures and representatives they are, was systematically subverted.
Burke's argument may seem insubstantial, yet he was right to distrust the French currency. For the Assignat was destroyed through hyperinflation. Napolean replaced the worthless currency with the Franc in 1803, shortly after he came to power.
If one were to argue in favor of fiat currency, one would be compelled to insist upon government restraint. So long as the government could be trusted to refrain from debasing the currency, even worthless paper could serve well enough for a period of time. But governments do debase the currency if those who govern believe it will serve their ends.
On a related note, our own master of the Assignats is to speak tomorrow night, before giving way to our Napolean who will also speak. The president's plan is irrelevant since the Republicans house will stonewall anything which originates from the desk of the chief executive. Bernanke could conceivably announce QE3, but I think this unlikely--at least for now. Regardless, we will be entertained by some fine political theater, after which the NFL season begins.
But if I were looking to invest, I would follow Burke, and move my fiat currency into "the two great recognized species... that represent the lasting, conventional credit of mankind."