Leading article: Precautionary principle

It's sod's law, isn't it? No sooner has the Government announced the mobilisation of the Royal Navy to rescue stranded British citizens, than the worst of the volcanic eruption in Iceland appears to be over. Last night there were hopes that the hundreds of thousands of travellers trapped by the closure of much of Europe's airspace would soon be on their way home. That so many personal dramas may be drawing to a welcome end, however, does not mean that there are no questions to be asked. In some ways, the bigger inquest is only beginning.

As two days' delay extended into four and five, travellers, airlines and travel companies began to ask why so much airspace was closed for so long, and whether such a blanket ban was really necessary. There will be questions about whether airlines and travel companies complied with their legal obligations, where these exist, to provide accommodation and sustenance.

There will also be fights about compensation, with most insurance companies treating a volcanic eruption as an "act of God" – and so uncovered – a view that is hard to contest. Airlines and travel companies, which have suffered huge losses from the disruption just as business was starting to pick up, will step up their claims for government support. If the worst delays are over by the end of the week, we suspect such claims will not meet much sympathy. Healthy businesses, like anything else, must, to a degree, cater for the unexpected.

While all these are considerations that deserve to be aired, however – and we do not wish to underestimate the damage to business or the inconvenience caused to individuals – it is important to keep a sense of proportion. The dangers of volcanic ash are recognised by international aviation and rules were in place, which were speedily invoked and adhered to. The closure of British and much European airspace was announced and extended in an orderly manner. There were regular European consultations, and safety – as it should have been – was the paramount concern.

In the UK, the election campaign gave the airport closures an additional edge, and the Government can be accused of waiting too long to take action. But the Transport Secretary, Lord Adonis, generally spoke good sense. And while there is surely a case for reviewing the rules on flying and volcanic ash, that must be done in a proper, scientific manner, not in the heat of public indignation. This was a safety issue, and where safety is concerned, the Government and the aviation authorities are right to err on the side of caution.