During the lifetime of Jesus of Nazareth, the cross was an ever present reminder of Roman power. It wasn't anything religious at all, rather, a hated symbol of occupation, a weapon of psychological terror that spelt out of the cost of resistance and kept people frightened.
So why is it that Christians want to wear the cross as jewellery? After all, you wouldn't go round with a silver electric chair about your neck, or with a beautiful brocade noose. That would be astonishingly offensive. So why isn't a cross likewise offensive?
I suspect it's because we've forgotten what the cross was originally all about. It's become a dead metaphor, losing its association with humiliation and fear, and instead becoming some sort of club badge for people who call themselves Christians. Which is why even though I am a Christian I'm also uncomfortable at the way the cross is featuring in the row between British Airways and one of their employees.
Its true there's a freedom of religious expression side to all of this that must be taken seriously in a country that prides itself on tolerance and diversity. But many Christians like me remain deeply uneasy that the way the cross is being defended by some is transforming it into a symbol of cultural identity - as if defending the cross is about defending something called Christian England.
Those on the extreme right, for instance, seem to be using the defence of Christianity as cover for an attack upon multiculturalism in general and Islam in particular. For such as these, the cross has nothing to do the brutality of empire and, bizarrely, everything to do with the cultural politics of a little country that Jesus had never heard of.
In fact, the source of this theological mistake goes way back. When the Roman Empire converted to Christianity it was clearly unlikely that the cross would retain its anti-imperial significance. So it morphed from being a mark of the brutality of Roman occupation into the logo of the imperial cult itself. From this point on, the symbol of the cross became dangerously unhitched from the essential 'offensiveness' of the cross as spoken about by St Paul.
Which may be why, throughout history, the cross has been all too easily conscripted by various forms of objectionable propaganda. Like, for example, the way thirteenth century friars galvanised huge enthusiasm for the crusades by what was then called 'the preaching of the cross'.
Given all of this, Christians urgently need to offer a better account of the cross than simply that it's a badge of identity. And amongst the first things that must be said is that the cross is actually God's act of solidarity with the disgraced and the powerless. The real battle for the cross has nothing whatsoever to do with jewellery.