The Conservatives won the election, therefore Labour should become more Conservative. This in essence is the argument being pursued by the Blairite wing of the Labour party at the moment.

The chief proponent of this argument is the current second favourite for the leadership: Liz Kendall. Kendall pursued this point in front of a press gallery lunch yesterday.

"The reasons why we lost aren't complicated. They're simple," she said.

"We decided that the British public had shifted to the left because we wished it to be so."

She went on to suggest that "we didn't lose because of Ed's personality. We lost because of our politics."

Kendall insisted that the Labour party should instead back Tory reforms of public services, Tory proposals for a EU referendum and Tory backbench calls for more spending on defence.

Kendall's simple pitch has since been described variously by members of the lobby as "brave," "bold," "courageous," and "modernising". In reality it was none of these things.

Far from being courageous, it was actually exactly what her audience wanted to hear. To say as the Guardian's Andrew Sparrow did yesterday, that most members of the lobby "aren't Labour members" is like saying that most trade union leaders aren't card-carrying Tory activists. To stand in front of the lobby and back Tory policies is like standing in front of a room full of Lib Dems while backing electoral reform.

Well, @LizforLeader just blew collective lobby socks off. Will @andyburnhammp and @YvetteCooperMP come and do a turn in the Gallery next? — Joe Murphy (@JoeMurphyLondon) May 21, 2015

And far from being modernising, Kendall's pitch was the exact same one we've been hearing from the Blairite wing of the party for about twenty years.

The problem with this approach is that the world has moved on from when Tony Blair first became leader. Back then Labour won by pitching to the right, safe in the belief that Labour's core voters had nowhere else to go. That simply is no longer the case. As we have seen from the rise of the SNP in Scotland and Ukip in the North, Labour's core vote have been taken for granted for too long. Simply talking about 'John Lewis voters' while backing more private sector involvement in the NHS is not enough to win back all the millions of voters who have deserted the party.

The Blairite answer to these difficulties is to dismiss them and hope that Labour's problems in the north and Scotland will just sort themselves out. This is fantasy, as the Spectator's Isabel Hardman points out brilliantly in her report on Kendall's lobby appearance.

"Another weak point was Kendall's prescription for dealing with Ukip, which sounded nice until you thought about what she'd actually said, whereupon you realised she had produced a solution no more weighty than whipped cream. It focused on giving people hope for their futures, which is quite an easy and nebulous thing to promise."

Yet this whipped-cream simplicity is precisely what the Blairites believe in. As their leading commentator Philip Collins writes in the Times today: "Politics is a simple trade and it is the start of obsessive madness to devise separate, fine-grained strategies for different places… Labour needs to look for leadership and competence and then trust that those two virtues really do work everywhere."

Get in a Blairite leader with 'centrist' policies and the rest will sort itself out is essentially the argument. The fact that installing Jim Murphy as leader in Scotland failed to have any impact whatsoever is simply ignored. The fact that Labour are seeing massive swings against them to Ukip in the North is simply downplayed.

Now to be fair to Kendall and her supporters, the basic premise that Labour needs to win over more Conservative voters in the south is obviously correct. Without doing so they have zero chance of getting back to power. But unless Labour start to win back voters in Scotland, then Labour's hopes are equally lost. Doing both may not be very simple, but it is the complicated electoral reality that Labour now faces.

Of course it is far too early to expect any candidate to know exactly how Labour can jump the many towering hurdles in the way of a Labour victory in 2020.

But in order to find the right answer, you have to at least start asking the right questions. So far the Blairites haven't even begun.