The title says it all. There's not much to add. "Bond vigilante attack" is just another name for "bursting the bond bubble". And loosening monetary policy would do that.
Scott Sumner says we should "Never reason from a higher risk premium", and that we should "(f)irst ask why the risk premium rose". Fair enough.
Scott says "...it’s almost impossible to imagine a shock that would be expected to promote both a higher risk premium and a faster recovery.". I disagree. I find it very easy to imagine a shock that would promote both a higher risk premium on US government bonds and a faster recovery: the shock would be for the Fed to do something like what Scott wants it to do -- target NGDP. With currently tight monetary policy, US government bonds (and money) look safe relative to other assets. With a looser monetary policy, other assets would look less risky relative to US government bonds (and money).
Call it "decreasing the fear safety discount [thanks Phil Koop] on bond yields", if you like.
When Eno still had hair. Now my daughter is studying his theories at university.