It goes something like this - geopolitical developments makes investors nervous about prospects for growth so money flows out of stocks and into bonds as it looks for a temporary haven in which to ride out the winds of adversity.
Such moves by investors/traders become so reflexive, that they tend to occur with very little serious thought actually being given to the movement of funds. The idea is, move first, think second; after all, you don't want to be the last guy left holding the bag when the dust settles.
I do think however that this perception is changing and I might add, as taken a severe hit ever since the inception of Quantitative Easing.
Note the following ratio chart to see how poorly bonds have been performing when compared to gold.
In truth I think this is also a vote against the US Dollar since those buying US Treasuries are in effect voting for the Dollar.
