> So then we'd "loan" partners US dollars to buy our stuff? Other way around, they buy T-bonds -- i.e., "loan" dollars to the US Government. But the country i

> So then we'd "loan" partners US dollars to buy our stuff? Other way around, they buy T-bonds -- i.e., "loan" dollars to the US Government. But the country is still owed that money back - it's like a trillion dollar bank account. One could say China "lends" dollars to the Treasury, but it's also just as accurate to say they "deposit" dollars into the Treasury. It's all just words to describe the action of giving money to another party to hold onto temporarily. "Strong" currency means there's more demand for it. Demand is usually a function of what you can buy with the currency. When countries reinvest their dollars into T-Bonds, they are double dipping on establishing demand for dollars. On one hand, they are owed back the dollars handed over to the Treasury (thus, creating future demand for USD), and on the other, accepting USD for the sales of their goods/services induces demand for USD, since it is yet another good that can be purchased with USD. "Weak" currency means that there's less demand for it. Weak currencies tend to be those from countries that produce little in the way of goods and services, or they only produce commodities (like oil) that are generally traded in other currencies. A weak currency can be a benefit. Hence why so many countries seek to artificially weaken their currency (aka currency manipulation). They often do this by strengthening the the USD. Sell to the USA, accept USD from foreign trade partners, buy T-Bonds with excess currency. The market for USD is so damn big that this is often trivial to do unnoticed, like using ocean to fill a swimming pool. But economies like Japan and China eventually grew to the point where their currency manipulation had a meaningful impact on the USD and American economy, rising the ire of American politicians. You can read about the Japanese "lost decade" which was suspected to be the result of American politicians intentionally targeting the Japanese economy due to currency manipulation and a general fear that the Japanese would "take over the world." (you can see these fears highlighted in 80s movies) > How does a noob like me learn about these systems. Take an economics class. Eco 101 is kind of trash for understanding anything truly useful. But at higher levels, you get into mathematical models for the underlying systems that govern trade. Granted, it's a little more hand-wavy, since economists can't conduct experiments at the scale that physicists can. But there is generally some experimental data supporting the models (it just might be data collected on college students trading candy bars). You can read about what happened to the Swiss economy during the pandemic. They are a smaller economy that's been plagued by an absurdly strong currency. There's been a lot of reporting and research into the many factors contributing to the currency's strength as well as the impacts it has had on such a small country.