Liberal senate leader Nick Minchin was the last man talking yesterday, somewhat too firmly insisting that former foreign minister Lord Downer of Mayo might be on the verge of making an honest living outside politics. As of course he should.

Beneath the persistent niggle of Malcolm Turnbull’s impatient ambition and the running gag of Brendan Nelson’s frayed leadership, lies a more disconcerting reality for conservative politics: that yesterday’s men stubbornly refuse to yield the floor and move on from their positions of looming prominence on the conservative backbench.

Last week’s vaudevillian brain snap from Peter Costello and this week’s call for steely discipline (if not a jolly good caning and a cold shower) from Alexander Downer were proof of one overwhelming necessity: that the party must be cleared of this obstructive, distracting dead wood. Only with these shadows of former greatness gone can the real work of policy rebirth and firm leadership begin.

The likes of Downer and Costello at least owe their party that.