Leading article: Mr Cameron's high-wire walk to an unknown goal

David Cameron's first anniversary as Conservative leader has generated a noisy interest already. He has been the subject of many articles and interviews on the theme of his performance over the past 12 months. It is all in marked contrast to the gloomy silence that greeted his recent predecessors when they ended their opening years at the helm.

The flattering attention proves that Mr Cameron has passed two tests. He has shown a capacity to set the agenda, an essential skill for any successful leader. In opposition, a party cannot implement policies. Instead, it must seek to make waves through other means. Mr Cameron does so by highlighting issues not normally associated with his party. From the environment, to poverty and the causes of crime, he strides confidently on to progressives' terrain. He has even claimed provocatively that the NHS is his overwhelming priority. This has resulted in an unusual situation in which the Government has introduced many policies aimed at alleviating poverty and improving public services, yet Mr Cameron appears to be benefiting politically.

Such contortions help Mr Cameron pass a second test. For the first time since the early 1990s, the Conservatives are being taken more seriously. They are scrutinised as a possible alternative government, rather than as a fractious and irrelevant rabble doomed to eternal opposition. In 12 months, and in the wake of a third election defeat for his party, Mr Cameron has made a significant leap forward. As a result, he raises thorny questions. On a range of issues, Mr Cameron makes declarations that chime with the assessments of those on the progressive wing of British politics. Yet as far as he has any policies, Mr Cameron's remedies appear to be those of a traditional Conservative. He puts the case for a smaller state, tax cuts, the renewal of Trident and the need for more prisons. His shadow cabinet includes some of the strongest supporters of the war against Iraq from across the political spectrum. Such policies and attitudes make it harder to attract non-Conservative supporters.

But if Mr Cameron's policies start to match his warm words, it is not clear whether his party will follow with much enthusiasm. Polls suggest the core vote is starting to twitch. Some Conservative MPs also stir, warning that traditional supporters could stay at home or vote for fringe parties. The political narrative could become one in which the Conservatives are divided over Mr Cameron's leadership. Alternatively, Mr Cameron risks alienating the core vote without winning over many progressives. Mr Cameron walks a high-wire act - and the destination remains uncertain.

Yet he has no choice but to continue walking. The Conservatives have fought two elections on an overtly right-wing platform and made little headway. Some critics say Mr Cameron should be further ahead in the polls, citing the massive leads Tony Blair enjoyed in the mid-1990s. But Mr Blair faced a divided Conservative government traumatised by Britain's exit from the exchange rate mechanism and led a party that had undergone many reforms. Mr Cameron starts from scratch and opposes a largely united government that presides over a strong economy. There are few parallels.

In 12 months Mr Cameron will have fleshed out some policies. In doing so, will he reassure his core vote and attract non-Conservatives? Will it be clearer what the Conservatives stand for, or is the leadership too dependent on spin and gimmicks? How will Mr Cameron fare against Gordon Brown, who will almost certainly be the next Prime Minister? Mr Cameron has made real progress. But he cannot really be judged until some of these questions are answered by the time of his second anniversary.