The condescension rained on Angela Merkel's unilateral clampdown on speculators is misplaced.

The German chancellor is not naive about the workings of capitalism – she knows that democratically elected leaders are locked in a power struggle with financial markets over how the debt crisis is resolved, and on what timetable. Speculators are amoral and their tunnel vision goes no further than financial gain. They have no interest in the wider body politic, but the side effect of their actions can be to usurp the prerogative of governments, forcing them to take more draconian actions than they would wish.

It is true that speculators exploit genuine flaws, but they can wreak their own havoc by magnifying and accelerating events, inflicting more pain on innocent citizens in the process: just ask any Greek facing austerity measures. They create emergencies, when measured progressive and united responses to complex problems would be far better.

The credit default swaps holding eurozone governments hostage are opaque, unregulated and ripe for reform. A ban on naked short-selling is not the unprecedented, unworkable lunacy Merkel's detractors would have you believe. Hong Kong made it a criminal offence in the wake of the Asian crisis in the late 1990s, and officials there believe this has been helpful in the current crisis.

Despite the discrediting of the financial sector, a belief persists that markets are all-powerful. But allowing a free rein to speculators subverts democracy.

We may sometimes despair of our leaders but it cannot be right that they are trampled by unaccountable and unelected traders, acting purely for their own profit and with no thought for the wider social good.

Merkel was foolhardy to act alone – and the fact she went freelance at a time when unity in the eurozone is desperately needed is alarming in itself – but her instinct that the markets must be tamed is entirely correct. This is a battle that governments cannot afford to lose.