Why markets can never be made truly safe

a boring affair. Valuing assets and extending credit against them is the preoccupation of the mortgage banker and the repo trader, who arranges trillions of dollars a day in repurchase agreements for very short-term government bonds. This activity is called financial plumbing for a reason: it is crucial but unsexy. And like ordinary plumbing, you hear about it only when something has gone wrong.Now is one of those times. On March 16th the Swiss National Bank extended $54bn to Credit Suisse, backed by the bank’s collateral, in a move that turned out to be insufficient to save the 167-year-old institution. On March 19th America’s Federal Reserve announced it would reactivate daily dollar swap lines with Britain, Canada, the euro area, Japan and Switzerland. The central banks of these economies can now borrow dollars from the Fed at a fixed exchange rate for short periods, backed by their own currencies, and lend them on to local financial firms.