> as a trading currency between non-US countries If country A trades with country B, it'll either get paid or pay with country B's currency. Country A might no

> as a trading currency between non-US countries If country A trades with country B, it'll either get paid or pay with country B's currency. Country A might not be interested in country B's currency, so it can use the US dollar and a US institution as a proxy between the two. But that doesn't do anything to affect the value of the three currencies. It's simply a matter of convenience (these US dollars get exchanged back into currency A or B seconds after being purchased). What matters is how confident people are of their respective government, laws and institutions compared to the US. Would they prefer to hold assets in the United States or their own country, or country A or B.