No rational case for God = increasingly desperate attacks on atheists

[Cato]

That's exactly what he is saying. In the article all but two cases where he talks about secularism he is talking about it in a political context, there are, as I say, two exceptions, one where he talks about secular myths (his comment of secular ideology) and the other where he takes a brief look at some historical secular philosophy, but neither of these deviate from the political theme he is following.

Bullshit. You linked a 4000 word essay by Gray. Here are the 140 words that address the politics of secularism....

Nowadays most atheists are avowed liberals. What they want - so they will tell you - is not an atheist regime, but a secular state in which religion has no role. They clearly believe that, in a state of this kind, religion will tend to decline. But America's secular constitution has not ensured a secular politics. Christian fundamentalism is more powerful in the US than in any other country, while it has very little influence in Britain, which has an established church. Contemporary critics of religion go much further than demanding disestablishment. It is clear that he wants to eliminate all traces of religion from public institutions. Awkwardly, many of the concepts he deploys - including the idea of religion itself - have been shaped by monotheism. Lying behind secular fundamentalism is a conception of history that derives from religion.

Perhaps you should reread what you linked.