You wil recall that when the earthquake/tsuanmi struck Japan, a massive unwind of the Yen carry trade began as risk aversion escalated. In addition, there was anticipation of widespread repatriation of overseas Yen investments by Japanese citizens and businesses, especially insurance companies, to deal with the aftermath of that tragedy. The result was a surge in the value of the Yen, especially against the Dollar which resulted in a rare coordinated intervention effort by the Bank of Japan, European Central Bank and Fed all which sold the Yen and bought the Dollar in an attempt to stem its rise. They did exactly that with the yen plummeting 10% in value against the Dollar in about two week's time.
However, the currency bottomed out and had begun a slow climb higher retracing more than half of its losses about a month after the bottom was formed. While Japanese monetary authorities were taking notice, they were content to watch it meander sideways. Not until its surge that began in July did they show any signs of concern. Apparently the move past the former coordinated intervention effort was enough to get them to intervene once again.
This time they have gone it alone (ECB and FEd officials were of course notified) so it remains to be seen how effective this latest round of war between the BOJ and the speculators is going to play out.
Suffice it to say, it is this intervention which is responsible for the strength in the Dollar this evening as it had just had the props knocked back out from underneath it during the day session Wednesday once rumors of additional Federal Reserve monetary stimulus began circulating through the markets. While the Dollar is up sharply against the Yen, note what has happened as a result of this Yen intervention to the price of gold in terms of the Yen - it has soared to a another record high. It seems as if we cannot get enough monetary authorities trying to deliberately debase their currencies can we?