<p>Quantitative tightening has blurred the line between monetary and fiscal policy, leaving ministers accountable for decisions they cannot directly control</p><p>When Labour made the Bank of England <a href="https://www.theguardian.com/politics/1997/may/07/economy.uk">independent</a> in 1997, the idea was that the Bank set interest rates while the Treasury taxed and spent. Monetary policy was in Threadneedle Street, fiscal policy in Whitehall. But in August the Bank of England quietly slipped o