By Nick Assinder BBC News Online political correspondent

Maybe it is his military training, but by removing David Davis from his job as party chairman, Iain Duncan Smith has proved he is not afraid of a bit of blood.

The Tory leader clearly believes he needs a fresh, female face in central office to push through his reforms of the party.

And it is widely believed he thinks Mr Davis has been blocking more liberal reforms and has been failing to do his job of raising the party's morale and profile, in favour of raising his own.

Second, Mr Davis - the self-proclaimed "dark horse" in last year's leadership campaign - is charged with still harbouring ambitions to become leader. Mind you, if that was a sacking offence, half the shadow cabinet would have to go.

And, whatever the spin from the Tories, Mr Davis has now been demoted.

Covert campaign

A positive gloss is being put on the move - suggesting he will be up against the government's "big character", John Prescott.

But the actual nitty gritty of his new job puts it very much in a lower league than his previous one.

Mr Duncan Smith has not made the mistake of sacking him outright, but kept him in the shadow cabinet.

And, interestingly, Mr Davis did not do what many had feared and refuse another job in favour of pursuing a covert leadership campaign from the backbenches.

Mr Davis makes no bones about his ambition to one day lead the Tories - but positioning yourself for such a job from the Central Office bunker is hugely difficult.

It is no coincidence that no chairman in recent memory has ever gone on to lead the party.

Rubber chicken

Sacking Mr Davis outright would have given his profile a sudden boost as it would inevitably have been accompanied by media speculation about his leadership potential and Mr Duncan Smith's current standing.

Leadership campaign

It would have freed him up to pursue a covert leadership campaign from the backbenches if he so desired.

When Michael Heseltine exiled himself to the backbenches in the 1980s, he spent years travelling the rubber chicken circuit building a constituency for himself - and it very nearly worked.

Even if Mr Davis did nothing himself to encourage such a campaign, he would still have been the focus of dissent and every time Mr Duncan Smith appeared in trouble all eyes would have focussed on Mr Davis.

But by accepting a front bench job it appears Mr Davis has made the calculation that it will serve him better to remain near the centre than exiling himself to the backbenches.

That does not, of course, mean he has abandoned any leaderhsip ambitions - just look at Chancellor Gordon Brown.

But, particularly in the wake of his demotion, he will now have to be extremely careful to do nothing that can be portrayed as disloyal.