David Cameron's ministerial hirings and firings do not amount to a wholesale realignment of the Conservative Party.

Even so, the apparently more Eurosceptic flavour of the new Cabinet will be no boon to the No campaign in the Scottish independence referendum.

Mr Cameron has not suddenly wrapped himself in the Cross of St George. The arch anti-European, Owen Paterson, actually lost his job. However, the elevation of Eurosceptic Philip Hammond from Defence to the Foreign Office is a clear signal to Conservative backbenchers and to voters swithering between the Tories and Ukip that Mr Cameron intends to play hardball with the EU. The loss of pro-European Ken Clarke from frontline politics adds to that impression.

Mr Cameron has said that, if he wins the 2015 General Election, he will seek to renegotiate the UK's membership of the EU and put the terms to an in-out referendum. That of course is not a message that plays nearly as well in Scotland, where Euroscepticism is a minority pursuit, as it does in the Tory heartlands of the south east. Indeed, an ICM poll this week found that backing for Scottish independence would rise by three per cent if voters thought the UK was "very likely" to leave the EU. The potential impact of this week's Cabinet changes must be seen against that backdrop.

The First Minister was quick to pounce on Mr Hammond's appointment, saying that his promotion to Foreign Secretary "has put one hand on the exit door leading the UK out of the European Union". But is it true that the UK is closer today to leaving the EU than it was two days ago?

Certainly, Mr Hammond has indicated that, if the UK cannot renegotiate its membership to its satisfaction, then it should leave the EU. This goes further than Mr Cameron's stated position but much depends, as it always did, on those negotiations and whether a future Tory Cabinet would be satisfied with whatever concessions were won from Brussels; sufficiently satisfied to back them as the basis of the UK's continued membership of the EU. Were Mr Hammond still Foreign Secretary at that point, he would be personally invested in those negotiations and therefore perhaps more likely to back them. On the other hand, he might not be part of the Cabinet at all. In any case, all this applies only if the Conservatives win the next General Election and they are behind in the polls.

So it is far too early to be predicting the UK's exit from Europe on the basis of one Cabinet appointment but, at this point in the independence referendum cycle, it is perceptions rather than reality that matter. The Prime Minister has encouraged the perception that his Government has become more Eurosceptic. If the outcome of the independence referendum had been uppermost in Mr Cameron's mind, he would surely have waited until after September 18 to carry out his reshuffle. As it is, his ministerial shake-up, though unlikely to be critical to the campaign, does his side no favours, particularly not the Scottish Conservatives.

Meanwhile, another notable change to the Cabinet was the demotion of the controversial Education Secretary, Michael Gove. The privately educated Mr Gove, from Aberdeen, has made himself deeply unpopular among teachers, academics and education officials in England, whom he referred to as "the Blob". Their partnership having now ended due to irreconcilable differences, Mr Gove is contemplating his new, rather unenviable role defending Government policy on the airwaves, a job that puts him very much in the political line of fire. It has been a humiliating 24 hours for Mr Gove, but it may have helped Mr Cameron broaden his Government's appeal in the run-up to the crucial 2015 election.