When we say dollar will decline, are we saying that it is against just the ‘real’ stuff like gold/oil/houses, or also against other (fiat) currencies.
I’m not sure if your question is rhetorical? (If it isn’t and you really do not have an understanding of the most basic concepts in economics, then suggest you take a community college course in introductory economics)
A decline in the dollar is another way of saying we’ll have inflation. By definition, most things will cost more in nominal dollars. If your salary does NOT keep pace with that inflation (and it won’t for most Americans) then your standard of living will be falling. However, I’m also implying I believe the dollar will fall dramatically in value relative to a basket of foreign currencies. If the dollar is worth less in Chinese RMB, then one would expect every item imported from China will cost more in dollars.
Money is subject to the laws of supply and demand, just like everything. This is why Zimbabwe has hyperinflation. Let’s say that Zimbabwe had one trillion Zimbabwe “dollars” of their currency in circulation. The government leaders wanted to buy more things, pay salaries (and bribes) but obviously they didn’t have any sufficient positive net monetary in-flows. So they literally just printed money, and used that. When they, for example, double the amount of Zimbabwe dollars in circulation from one trillion to two trillion, guess what happens to the prices of everything? Do the math.
We are kinda saying the same thing could happen with the dollar, with shocks from both sides: 1) our government has in fact started printing money now, adding billions into circulation. 2) The world is trading out of dollars, dumping dollars for other currencies. This effectively INCREASES the amount of dollars per capita for those still using dollars, and increases the available dollars in circulation because of a glut of dollars in circulation for fewer dollar transactions.