KEY POINTS

Bond vigilantes are poised to wrest back power in 2018. For the first time in four years, the U.S., Japanese, euro zone and UK governments will together issue more net debt than their central banks will buy. That gives investors a welcome chance to hold profligates to account. But markets may be prone to over-reaction as money managers rediscover their rusty powers of discernment.

Combined net debt issuance by these so-called G4 economies will total $1.3 trillion, up by a third from the projected issuance for 2017, according to Morgan Stanley. The increase in supply will coincide with a decline in demand from central banks, which are expected to reduce their combined bond purchases. That makes for a watershed year in which net issuance will exceed official purchases of debt.