But what the federation and its affiliates are faced with is much more fundamental than whether President Jacob Zuma will be more suitable to lead the ANC beyond 2012 than, say, his deputy, Kgalema Motlanthe, businessman Cyril Ramaphosa or Human Settlements Minister Tokyo Sexwale.

As they celebrated Workers' Day yesterday, Cosatu leaders would have gone out of their way to demonstrate that unity was still strong within their ranks.

But sceptics would argue that the manner in which Cosatu and the ANC alliance leaders were deployed to various rallies yesterday reflected the divisions as the ANC's elective conference in Mangaung gets closer.

They would ask why, at what was billed as the "national rally" in Bloemfontein, Cosatu wasn't represented by its most prominent official, general secretary Zwelinzima Vavi.

Instead, president Sdumo Dlamini, the second-most powerful leader in Cosatu, shared the stage with Zuma and SACP general secretary Blade Nzimande.

Could this have something to do with the claim in various media that Vavi and Dlamini hold different opinions about whether the trade union movement should back Zuma's bid for a second term?

Perhaps.

But to reduce the differences in Cosatu to a personality clash between its president and its general secretary would be to grossly downplay the policy choices confronting the trade union giant.

Eighteen years into democracy, the union movement finds itself in a difficult conversation with itself about its future and its relationship with the ruling party.

With two years to go before South Africa reaches 20 years as a free and non-racial society, organised labour has to ask itself if the alliance with the ruling party has been of benefit to the working class and whether, if it continues in its current form, it will bring about the radical economic changes Cosatu would like to see.

The majority of Cosatu affiliates seem in agreement that the alliance with the ANC and the SACP should continue, but there is disagreement on how it should be configured going forward.

As they stand at the crossroads, unions such as the National Union of Metalworkers of SA are agitating for a left turn, arguing that trade unionists should swell the ranks of the ruling party and ensure that their leaders dominate in the new ANC national executive committee that will be elected in Mangaung.

This approach also involves removing from the NEC those leaders perceived to promote the conservative and pro-business economic policies preferred by government for the past 18 years.

It is a strategy that the labour federation adopted in the run-up to the ANC's Polokwane conference five years ago. It failed spectacularly, largely because the federation's leaders were so consumed by their efforts to ensure a Zuma victory that they neglected to ensure that worker leaders made it onto the NEC.

This year, the strategy is likely to face stiff resistance from ANC members who resent what they call an attempt at "organisational capture" by Cosatu.

If the outcome of the Nelson Mandela metro ANC regional conference - at which a Cosatu-backed Zanoxolo Wayile failed to garner enough support to be nominated as challenger to incumbent chairman Nceba Faku - is anything to go by, the chances of this strategy succeeding are as non-existent as a Doctor Khumalo-coached Kaizer Chiefs winning the Premier Soccer League.

The Nelson Mandela metro, which encompasses Port Elizabeth, is a strong working-class base and if a unionist can't win an ANC election there what hope is there elsewhere in the country?

And then there are the likes of the National Union of Mineworkers and other Cosatu affiliates whose leaders are closely linked to the SACP leaders.

This group believes in continuing along the route Cosatu has taken for much of the past 18 years - forming tactical alliances with the key ANC leaders they consider to be more "progressive".

By backing particular leaders within the ruling party these unionists believe that labour's voice would carry more weight in the corridors of power once those they helped to win take office.

The experience of the last five years, however, shows that this approach, too, leads to a cul-de-sac.

Once in office, even those who are indebted to the federation for their political fortunes tend to say they are there by a "broader mandate" of the "broad church" and do not to represent "the narrow interests" of the labour movement.

There is also a tiny minority that is agitating for Cosatu to form a "Labour Party" and go it alone. These, however, are insignificant voices that are unlikely to gain momentum for at least another five years.

Besides, the experience of a number of trade union-backed labour parties in Southern Africa over the past 20 years has not been inspiring. They have tended to be as corrupt and undemocratic as the "nationalist" movements they sought to replace.

A more realistic option for Cosatu would be to revive the idea of an election pact with the ruling party. The problem all along has been that the labour movement tends to give a blank cheque to the ANC during elections. All it insists on is that a few of its former leaders are appointed to the cabinet and others made MPs.

To put an end to the love-hate relationship that has been the state of the alliance for the past 18 years, and given that Cosatu won't break away from pact, it is time the federation put the reconfiguration of the alliance back on the agenda to ensure it has a more meaningful voice.