The rumours were circulating over Easter. Malcolm Turnbull had decided not to recontest Wentworth; he was gutted by what had happened, especially Abbott’s refusal to have him back on the frontbench, and was pulling the pin. This morning he announced it — on Twitter, ever the digital native.

Some of his colleagues will be happy. Like Peter Costello, Turnbull’s mere existence on the backbench was destabilising. Tony Abbott will be happy for the same reason. But his pleasure will be tempered by the fact that Turnbull’s departure means the Coalition is one seat further from victory. Wentworth will be very difficult to hold unless the Liberals find and field a progressive, environmental-minded, gay-and-lesbian-friendly candidate.

If Labor fields a strong, high-profile candidate — anyone but George Newhouse would do for a start — the Liberals will struggle. Better yet, a high-profile independent could make a strong showing — and if they managed to beat a major party candidate on the primary vote, they could snatch the seat on preferences.

There’ll be happiness in Labor ranks, as well. There’s a view that if Turnbull ever returned to the Opposition Leadership, chastened by his first time around, he would be a far more dangerous opponent, especially against an ageing government. Now that threat has been removed.  But some will rue the departure of a foe that brought much to politics.

Ultimately it was Turnbull’s meteoric rise that did him in. Remember this is only his second term in Parliament. Despite spending seemingly his entire adult life in the public eye, he was never a political native, even after he seized Wentworth from Peter King by main force. Becoming leader of his party less than four years after arriving in Parliament — like his predecessor John Hewson — meant he arrived in the top job without a strong support base within the party and without the sort of skills that politicians develop as they move up through the ranks.

And one of those skills is keeping up communication with backbenchers once you reach the exalted ranks of ministerial office. As became very clear once the political agenda shifted to a divisive issue like climate change — which had already cost Brendan Nelson his job — Turnbull’s huge intellect — no one ever questioned how brilliant he is — was clearly not matched by his capacity to communicate with his backbench, beyond haranguing them in radio interviews.

And yet he was learning. On climate change, Turnbull set out to achieve what many thought was impossible, to drag the Coalition to the point of backing the Government’s CPRS.  His main tactic was uncharacteristic patience, albeit with the occasional brain explosion when his frustration got too much for him. The media, particularly the conservative media, mocked him for trying, but he came within a single vote of pulling it off after months of subtly shifting the goalposts to the point where a large number of Coalition MPs were no longer prepared to resist the idea of voting for the CPRS before Copenhagen.

A future Turnbull leadership would have profited from that experience. It might have been a more boring Malcolm, one less prone to colourful radio interviews in which he attacked his own MPs, but it would have shored up his undoubted intellectual brilliance.

And that, ultimately, is why the Liberal Party is the real loser from his departure. In Opposition, the Liberals are an ideological mess.  Tony Abbott, heir to the John Howard tax-and-handout tradition, is every bit as much at odds with his party on some issues as Turnbull was. Conservatives and liberals can barely disguise their animosity on some issues. Bereft of the discipline of office and the leadership dominance of John Howard, it’s no longer clear what the Liberal Party stands for — even on something as core to Liberal philosophy as small government.

No one in the Coalition’s ranks appears to have the strategic intellectual capacity to address that. The only candidate is Andrew Robb, and Robb’s strengths are primarily tactical, not strategic. Joe Hockey may yet develop some substance, but he’s yet to impose himself intellectually, and in any event he still appears in a funk after the leadership spill.  Tony Abbott, whose intellectual development in Battlelines looked promising, now  appears to have retreated to mimicking John Howard.

Maybe the next generation — Paul Fletcher, Jamie Briggs, Greg Hunt, Scott Morrison, Kelly O’Dwyer — can chart an ideological path forward for the conservative side of politics, but only Turnbull looked up to the task, provided he could assert his leadership authority. Now we’ll never find out.