Treasury just admitted it can't let 30-year yields run

The 30-year Treasury yield hit 5.31% last week, its highest since 2007, before the Treasury Department stepped in and said it would double its buyback of longer-dated debt, from roughly $2 billion to $4 billion, running from September 9 to November 4. Yields eased to around 5.18% on the news. That's real relief, but it's a rounding error against total outstanding issuance, and a $25 billion 30-year auction on August 13 still cleared at 5.22%, the highest since 2001. Every basis point on the long end feeds straight into mortgage rates, infrastructure financing and corporate borrowing costs across the UK and Europe too, since Treasuries set the global risk-free benchmark. Canada's 30-year yields hit levels last seen in 2010 and Germany's touched 2011 highs in the same selloff, confirmation this is no longer a US-only fiscal story.