The implementation of the Volcker rule has forced investment banks out of the business of trading on their own account in the US bond markets, an activity they often described, rather benevolently, as “providing liquidity”. A considerable lobby industry has emerged to push back against these new regulations, as has a narrative that - without their involvement - these markets will stop functioning properly, particularly during times of stress. Indeed JPMorgan’s Jamie Dimon recently described volatility in the treasury market as a “warning shot” as to what may lie ahead (despite the fact that trading in US government bonds is one of the many areas the banks successfully lobbied to remain exempt). Providing liquidity in markets is a profitable business and financial markets today are highly competitive. Where the investment banks are stepping back, a raft of specialist players will be stepping in. The key difference will be these new players are not backstopped by tax payer money. That the banks are complaining is probably a great bellwether that important changes are underway.