system
Given the following post, respond as if you're commenting on Reddit:
human
What is the downside for the US of having the US dollar as the world's reserve currency?
gpt
It means that the US is effectively in charge of a global monetary union in some sense. This is called the "monetary super power hypothesis".

You may have heard the whole "savings glut" explanation of 2008. Well the MSPH says that the savings glut was caused by the Fed recycling it's own monetary policy decisions. The Fed doesn't seems to be taking this effect into account when it's making decisions.

It should be noted that this isn't necessarily bad for the US as long as it conducts monetary policy with this effect in mind. It is bad in that the "dollarzone" is not an optimal currency area and therefore its causing global economic instability.