• Out of power since 2010 and with two consecutive election losses behind it, Britain's opposition Labour Party badly needs to reshape itself, if it is ever to return to government.

But the party is now threatening to tear itself apart as it heads into a leadership contest next month.

All indications are that Labour is about to elect Mr Jeremy Corbyn, a man even more left wing than Mr Ed Miliband, who quit as party leader after its drubbing in the May general election.

Mr Corbyn, with the staunch support of unions, is a man who will take Labour even further to the left of the political spectrum, condemning the party to opposition until at least the middle of the next decade.

Unlike Britain's ruling Conservatives who spend little time arguing about political ideas and more on picking leaders who have a good chance of winning general elections, Labour has a tradition of anguishing about its ideology every time it is out of government.

This is largely because the party consists of two main camps, pulling in different directions.

On one side are the old trade unions, slowly declining in membership but still determined to keep the party which they finance solidly on a left-wing agenda, advocating more taxes and more government spending.

In the opposite camp are the so-called Blairites, named after former premier Tony Blair, who argue that for the party to win elections it must win over the large middle ground of voters, much more likely to be attracted to any party which convincingly promises lower taxes and a growing economy.

Labour is faced with an intractable problem: no leader can be elected without the support of the trade unions, but no leader can become prime minister without reaching out to a broader electorate.

Matters are complicated by the outcome of the May general election. Not only did Labour fail to attract more than a third of the voters, but the party was also annihilated in Scotland, a former stronghold.

Winning Scotland back is a necessity for Labour as without the approximately 50 Scottish parliamentary seats, the party has no hope of gaining power.

In theory, Mr Corbyn, 66, is perfectly suited for this task. He has impeccable anti-establishment credentials. When Labour was last in power, he defied his own government by voting against it no fewer than 238 times, something which goes down well with Scottish voters, who mistrust the London-based establishment.

Like most Scots, he supports the renationalisation of Britain's railways, the abolition of tuition fees in universities, the closure of selective schools for gifted children, and "squeezing the rich" on taxes.

He also wants Britain to abolish its monarchy and give up its nuclear weapons, other policies which may play well with some in Scotland.

But Mr Corbyn also wants Britain to engage in "peace talks" with Al- Qaeda and other terrorist networks, and for the British government to demand the abolition of a dog-eating festival in China.

The snag is that such policies have zero chance of being supported in England, where more than 500 out of the British Parliament's 650 seats are to be found. "The world is not ready for his sandals and socks," concluded an editorial in The Guardian, a newspaper traditionally sympathetic to Labour, referring to the attire traditionally associated with impractical left-wingers.

Even talk of Mr Corbyn becoming leader has already hurt the party. Opinion polls conducted earlier this week indicate that three-quarters of Britons think Labour is less electable now than it was at the May elections.

Still, Labour's trade unions fervently support Mr Corbyn.

"His message has resonated with public sector workers who have suffered years of pay freezes, redundancies, with too many having to work more for less," says Mr Dave Prentis, the boss of Unison, which has 1.3 million members.

Support also comes from many individual Labour members, who regard Mr Blair - Labour's most successful recent leader - as a "traitor" to the party's "true" ideology. Internal Labour polling indicates that Mr Corbyn is now about 20 percentage points ahead of two more centrist candidates vying to lead the party.

Much can change before the leadership vote scheduled for Sept 12. Still, Labour's predicament is shared by other European socialist parties. All have ceased to be mass political movements, and are now dominated by a core of people, who are increasingly unrepresentative of voters at large, and tend to pull these parties further to the left.

And all socialists are faced with a globalised economy in which the old left-wing ideological recipes are no longer workable.

The dilemma for Britain's Labour and its soulmates elsewhere in Europe is real enough. But so is the reality that, unless they come to an accommodation with the market economy and with the aspirations of today's voters, they are increasingly unelectable.