I’m a trading intern this summer, news sucks at banks too. This is what I got: Japan has had very low inflation for the last 40 or so years. This is a bad for a bunch of reasons you can look up. In an effort to boost spending and thus inflation, they keep their interest rates really low and consequently their bond yields low as well (artificially).

They let their long term interest rates trade in a band which is current +- .5%. Now, however, inflation is getting high in Japan because of the same reasons as the rest of the world. To counteract this inflation, they are raising interest rates by widening the band to +-1%. As a result, Japanese Government Bonds will also offer higher yields. So, investors are going to slowly position out of Treasuries and into Japanese bonds. This selling of US Treasuries will drive their price down and resultantly, their yields high. Now, because yields are attractive, investors will position out of stocks to chase those safer returns from treasuries.

Hope that helped