I didn't say government reserves would save the country, I said personal, private reserves would save the country. A person that owned $10,000 worth of gold before a Tunguska event over Washington would still get at least $10,000 worth of necessities from anyone for that gold and so there would be a semblance of an economy, and therefore protection from the National Guard. A person that that had dollars wouldn't, and couldn't participate in that protection. I do believe that the states and Washington should keep gold on hand though, of course.
As for supplies, they aren't kept in DC, and the value of any currency is a measure of the confidence of its users.
But the ditribution of those supplies depend on a stable monetary system. Gold is the most stable in catastrophic situations because rarely if ever has the entire world gone through a catastrophy at the same time. Paper fiat money almost always would fail even in a localized catastrophy. That confidence in cotton paper and green ink would evaporate immediately with the the leveling of Washington.
How much more confident would most Americans be without little Tommy Daschle trying to raise their taxes?
There's more to the government than Little Tommy.