The author is an FT contributing editor

This week the US is once more negotiating with itself to ensure the federal authorities can proceed borrowing. The stakes are acquainted. And but this time there appears to be extra concern that the greenback itself is in danger — that everybody else, lengthy annoyed with the US forex, may take the prospect to cease utilizing it.

The issue with that argument is that there isn’t a such factor as the greenback. There are a lot of completely different sorts of {dollars}, every with its personal qualities. No financial regime lasts perpetually. However financial regimes aren’t collective delusions, both. {Dollars} is not going to all instantly blow away like smoke if Argentina begins pricing soyabeans in renminbi. Every type of greenback has its personal worth, and we ought to be exact about which of them are in peril.

Usually once we discuss a forex we really imply financial institution deposits. Greenback power is a measure of the will amongst forex merchants to swap deposits in another nation for deposits within the US. The Federal Deposit Insurance coverage Company has made it clear by means of repeated crises that it’ll not let any deposits fail, interval.

There isn’t any different forex with something just like the FDIC’s express assure of $250,000 of deposits, or its implicit assure of evidently just about something. Eurozone financial institution deposits, for instance, are backed solely by nationwide governments, and solely to €100,000. You could not like American financial institution {dollars}, however there isn’t a forex which may conceivably change them.

There are additionally eurodollars — dollar-denominated deposits at international banks. These, too, take pleasure in an virtually express assure from the Federal Reserve, by means of agreements to briefly swap currencies with international central banks in a disaster. No different central financial institution presents something remotely similar to the reassurance of those swaps. You may not like this method, however once more, it’s not clear what may change it.

In monetary markets, treasuries perform as {dollars} — they aren’t simply denominated in {dollars}, they’re {dollars}. If the federal authorities begins to overlook funds, the worth of successive runs of treasuries may dip under par. That, in flip, would eat away on the market values of even accountable asset portfolios. It could be unhealthy. Treasury {dollars} are in danger.

Beginning at the least with the Financial institution of England’s constitution in 1694, nevertheless, sovereign debt has remained the bedrock of the worldwide monetary system. You could not like this method — I’ve some questions on it myself — however it’s the one we now have. And right here, sheer quantity is an under-appreciated power of the treasury greenback.

People consider treasuries as debt, and measure them as a share of gross home product, to allow them to argue about what sort of debt load could be sustainable. However as Michael Pettis factors out, everybody else on the earth thinks of treasury {dollars} as belongings, and no different nation has been prepared and in a position to produce sovereign debt belongings at something near America’s quantity.

Add up native and federal authorities borrowing and America had pushed $26.9tn in sovereign debt belongings into world monetary markets by September of 2022, in keeping with the newest comparative knowledge from the Financial institution for Worldwide Settlements. (Sure, I do know the Fed additionally holds treasuries.) China and Japan come subsequent, with simply over $8tn every in sovereign belongings in their very own currencies. Only a few different nations even measure their sovereign debt in trillions.

We consider America’s capacity to borrow within the mighty greenback as a privilege, nevertheless it’s attainable the other is simply as true. America’s enthusiastic willingness to borrow helps make treasury {dollars} mighty. You could not want to maintain treasuries in your portfolio. That’s high-quality, however what else are you going to carry?

All of those {dollars}, collectively, assist clarify the “invoice of lading” greenback — shipments of products overseas, priced in {dollars}. Conventional forex theories argued that items had been priced within the currencies of the place they had been coming from or going to. More moderen work has identified that exporters choose dominant currencies, as a result of secure costs are extra vital than sovereign forex benefit.

Greenback costs on payments of lading are secure, in flip, due to all of these other forms of {dollars}. You possibly can consider that oil priced in {dollars} is only a product of American plane carriers, however the petrodollar alone doesn’t clarify the worldwide proof of dominant currencies.

There are a lot of causes to be sceptical of whether or not sturdy {dollars} are good for America. All these treasury gross sales don’t appear to have paid for a lot productive funding, simply periodic tax cuts and stimulus programmes. However you don’t have to love all of those {dollars} to see that it’s under no circumstances clear what the opposite selections are.