Why is paper money declining in value? To quote Voltaire, “Paper money eventually returns to its intrinsic value – zero” While there is a limit as to the amount of silver available in the Earth, there is no limit on how much paper currency the government can print. And paper money has no intrinsic value. As more & more is printed, its value naturally declines toward that zero.
What ultimately matters for any kind of good you can use as numeraire for transactions is whether or not other people will accept it for transactions.
In the case of the US dollar, you are looking at a country with its own currency and a central bank which has shown over the last 40 years that it is committed to stabilizing prices. The Federal Reserve Board doesn't strike me as an organization that would let inflation rise in the two digits. Whether it can act to choke inflation is not even a question. I mean, you can doubt that it can increase inflation because nominal interest rates cannot become infinitely negative. On the other hand, there is no limit to how high they can increase interest rates should it become necessary. It could trigger a large recession, but it's quite obvious inflation would at some point fall with sufficiently large increases in the interest rates. You might, on the other hand, doubt their commitment to stabilizing price dynamics.
The other point here is that your US dollars have a guaranteed use that you probably never thought about: the IRS collects taxes in USD. As long as the government wants USD, you have a clear use for the USD.
I don't have all my assets in junk silver. I have an increasing amount of it, along with vintage gold coins, vintage silver dollars & cash money in the bank as well as a nice monthly income. But I see a stock market bubble of even greater proportion than the 'dot com' bubble. And I see a Federal Government careening out of control, led by manipulators & incompetents. I don't see the near future as being very bright. I hope you see the same thing & take precautions along the lines I mentioned.
If you really believe there is a large stock market bubble that will bring down everything on its way to the graveyard, there is a cheap way to profit from the fall: take some money and buy way out-of-the-money put options on the S&P500 or some other market index. If you're wrong about timing or even about the event, you lose peanuts (because you need a sick fall in the underlying to make money, they tend to be cheap) -- and, more importantly, a maximal amount of peanuts that is known in advance. But if you are right, you make bank on it.
I never take people who forecast an apocalypse seriously. You're not the first one to shout "the end is nye," and it is no wonder the history of those screams is fraught with literally 100% of mistakes since it involves tail events. More to the point, what do you stand to lose if you are wrong? You have a very conservative investment strategy and, well, good for you. But why should anyone listen to your doomsday forecast? Virtually nothing will happen to you if you're wrong: you'll just lose small gains in assets you probably would not have bought anyway. That is another thing I kept repeating about Peter Schiff back in 2008 and 2009 when he warned of hyperinflation: show me your portfolio. My personal guess: he would not have staked a coffee on that bet. Another personal guess: he had a lot of gold in his portfolio and he was trying to prop up the price of his own assets.
As for my portfolio: I am a Ph.D. student so, besides physical goods, all I own is cash (Canadian dollars, to be precise). Short of my car, books and some clothes, all I have is staked on CAD not becoming worthless. Some form of currency has been around for centuries, so I would bet it will be around for a few more centuries. It used to be more metal, but banknotes date way back my friend. The only instances we have of what you talk about involved governments literally monetizing their debt -- and I don't think either the US nor Canada is anywhere close to that. But, hey, stock up on silver if you like.
