The bond market "vigilantes" of old used to bully wastrel governments. Now they appear to have moved on to a grander target — the US Federal Reserve.

Traders are betting that the US central bank is certain to trim interest rates when it meets this month. Whatever doubts remained were largely dismissed by Fed chairman Jerome Powell on Wednesday, when he focused on persistently low inflation in the world's largest economy, and a fading global growth outlook.

But the prospect of monetary easing still looks odd when set against mostly decent US economic data. Richard Barwell, head of macro research