As European policymakers ponder what action to take to halt the slide in the value of the euro, officials in Washington are studying the awkward question of whether the mighty US government, with its enormous potential to influence markets, should also get involved.
Foreign exchange traders and some European officials themselves have interpreted recent remarks by Mr Larry Summers, the US Treasury Secretary, as an indication that the US has decided to wash its hands of the European currency. But this view is based not on any public statements but on what may be some misinterpretations of the view from Washington.
A number of European officials believe US participation in co-ordinated intervention to prop up the euro would make that intervention much more effective than if the European Central Bank were to operate alone. But, according to some reports that have emerged from this week's meeting of Euro-11 finance ministers, some European policymakers believe the US is unwilling to get involved, seeing the sharp fall in the value of the European currency as a market-driven "euro problem" that has been driven by weak European growth relative to US growth and not something in which policymakers, at least not US policy makers, should intervene. Economists believe there are strong reasons why the US might not want to intervene.
A strong dollar has been helpful in keeping a lid on inflationary pressures at a time when domestic demand has threatened to run out of control.
"A weaker dollar runs counter to the grain of current policy of trying to slow the economy," said Mr Ray Attrill, director of research at economic consultancy 4Cast. "The Treasury will be interested in limiting the need for interest rate rises in an election year."
Whilst the dollar's rise against the euro has led to a widening of the US trade deficit with Europe, the gap with Europe is a relatively small proportion of the overall shortfall.
In public comments, Mr Summers has, of course, refused to talk directly about US attitudes towards currency levels.
When asked about currencies, he restates what he calls the need for governments to focus on the so-called "fundamentals".
But there are several ways in which these constantly repeated remarks may have been misinterpreted to suggest that the US is indifferent to the euro's value.
Many European policymakers see Mr Summers's strictures as pointed directly and critically at what the US sees as Europe's need to promote more flexible labour and capital markets, (along the lines of the US model). But Mr Summers has emphasised that the US also needs to improve its own fundamentals by, most importantly, raising its savings rate.
Second, while the Treasury has said governments should address fundamentals in seeking to redress global economic imbalances, that is not the same as saying that currency markets are always driven simply by fundamentals or that they never overshoot.
On two critical occasions in the last five years, intervention to drive the value of the main currencies was needed and likely to be effective.
In April 1995, after the Japanese yen had reached Y80 to the dollar, and then again in June 1998, when it approached Y150 to the US dollar, the US combined with the Bank of Japan and other main central banks to push currencies back towards more appropriate levels.
So what are the implications for the current situation? Though currency market movements are driven by a complex mixture of factors that are all but impossible to disentangle, on both those occasions, US officials reached the judgment that markets had probably overshot, and could be nudged back towards more appropriate levels.
Both were accompanied by policy actions to address the underlying economic imbalance.
A number of factors explain the euro's 25 per cent depreciation since its inception against the dollar - the weakness of underlying, or potential growth, in Europe compared with the US, demand in the US for savings to finance its technology-driven investment frenzy, and market uncertainties about the credibility of the new European monetary policy framework.
Yet, while it has pressed for action to address the underlying problems, the US has said nothing that indicates it is indifferent to sudden movements in currencies.
