THE subtle gravitational influence of the moon is imperceptible to humans yet is able to move oceans. Discreet changes to the rules governing European finance may in time have profound effects on the tides of capital that wash its shores.

On January 1st three new European regulators will begin for the first time to exert centralised control over large swathes of Europe's financial markets—including the City of London, the world's biggest international capital market. The new bodies succeed three committees that previously tried to co-ordinate the supervision of European banks, insurers, pension funds and securities. Yet unlike their predecessors, these are no mere talking-shops.

The new rules will bring things such as credit derivatives and credit-rating agencies into the regulatory net. Officials concede that a lack of rules did not lead to the last crisis, yet they fret about the next one. “We are trying not only to fight the last war, but also to anticipate the sources of the next one,” says one senior Eurocrat.

From January, for instance, the European Securities and Markets Authority (ESMA) will directly supervise ratings agencies. Proposals currently being debated may also allow it to intervene directly in markets by, for instance, temporarily banning naked short-selling (the sale of securities that investors do not yet have in their possession). A European Commission discussion paper seen by The Economist asks whether ESMA should be given the power to ensure the “appropriate timing” of the publication of sovereign-credit ratings. Some fret that might be shorthand for suppressing cuts to the ratings of wobbly European states.

The new rules also centralise authority that is now exercised (in theory) by national supervisors. “We see [the new agencies] as being the supervisors of the supervisors,” says one official. “Some national supervisory authorities failed dramatically. We know that in Ireland there was almost no supervision of the large banks.”

Quite how this will work is not entirely clear, partly because the rules are still being written. But considerable power will be given to the new authorities to write “binding technical standards” which national regulators will then have to enforce. “We have very little residual rule-making capacity,” says one regulator.

Many national supervisors, including those in Britain, which has in the past opposed any European encroachment on how the City is run, are reasonably sanguine about these developments. Although there is some anxiety about the erosion of sovereignty Europe's new financial landscape entails, the rules are widely seen as likely to make the whole financial system safer. Many large insurers and banks, in London and elsewhere, also stand to benefit from common rules across Europe's borders.

Yet there are two big concerns. The first is that the new rules threaten to politicise issues that were, in most cases, happily looked after at home. The commission “wants to create an ever closer union,” says one person involved in the talks. “That's in their DNA and the crisis provides a good opportunity.”

This is a particular worry for London. Although Britain has the largest stake in getting the new rules right, it will have no more say in drafting most of them than countries with far less economic interest in the outcome (see chart). In the tortuous world of Brussels horse-trading, Britain may have to make concessions on all sorts of side-deals to win support for sensible regulation of one of its main industries. “Nonsensical decisions may be taken by majority vote on things that are really about the UK,” says Nicolas Véron of Bruegel, a pro-European think-tank, who supports the centralisation of regulation but frets about the new bodies' governance. Commission officials counter that a collapse of, say, a big hedge fund in Britain could spark contagion throughout the rest of Europe; that gives all countries an equal stake in how the rules are written.

The second big worry is that the new rules exacerbate risk by taking powers away from the authorities that would have to pay the bill if things went awry. In the area of derivatives, for instance, ESMA and its banking counterpart, the European Banking Authority, will write detailed rules over how much capital and margin centralised clearing houses should hold. Yet were a clearing house to blow up, national taxpayers would be the ones bailing it out. That really would make waves.