Comment by eigenspace

Euro countries hold even more US bonds than Japan does, and could sell those if they need to.

But the EU probably wont do that for monetary reasons. First, the EU doesnt really mind too much if the Euro drops in value a bit since it somewhat helps domestic industry. Second, the Euro seems to have strengthed against the dollar, not weakened since this was done.

I think if there was a coordinated selling off of US treasuries by Euro countries, it'd be to force a political concession from the USA, not to defend the Euro's value.