John Bruton and Bertie Ahern have more in common than perhaps they realise. Both have been at or near the top in politics for a great many years. Both have been respected while holding the office of Taoiseach, and derided as opposition leaders. Both have served in the Department of Finance in difficult times (although one managed to keep his head down better than the other).

Both enjoyed a relationship with a previous leader of high charisma (again, one was perhaps more diligent in his loyalties than the other). Both have known the bitter taste of having the top job taken from them in an unexpected way, Ahern in 1994, Bruton in 1997.

There is one other similarity which at the same time marks out a good part of the difference between them. Both have given their lives to politics from a very young age. Bertie Ahern marked his 21st year in Dail Eireann last year, and John Bruton his 30th this year. They're no more than a couple of years apart in age, and yet Ahern looks and seems far younger, on the one hand, and far older and more experienced on the other. Why?

It starts with the way they learned their politics; one from the street, the other from a sense of noblesse oblige. One was steeped from the very beginning in the day-to-day problems and issues of a tough, inner-city constituency. The other immersed himself in history, economics and the traditions of his rather more gentlemanly party.

One, as a result, is intimately in touch, and instinctively knows the popular mood, often before the populace has figured it out. The other knows what's good for us, because that's the way he was bred.

And that's a good part of the reason people think Ahern is one of us, and Bruton is one of them. For all they have in common, they couldn't be more different.

People see their respective dedication to politics in a totally different light. It's a bit like the animals that supply our bacon and eggs in the morning. The hen is involved in the exercise, but the pig is totally committed. From this perspective (and no disrespect!) Bruton is seen as the hen, and Ahern as the pig.

And that's a tragedy for John Bruton, because it is also a travesty of the truth. Bruton is an honourable, decent man, bubbling with ideas and energy (although he does have a stamina problem). He has many of the qualities of statesmanship, qualities he displayed to considerable effect during his period as Taoiseach. He has character.

And yet, in not far short of a decade as leader of the second-largest party in the State, he has nearly always failed to inspire. On the set-piece occasions in the Dail where an opposition leader can make his mark, he always seems to miss the moment. In fact, he never seems to be himself, almost as if he's ashamed to show people what he's really like. There's a lack of confidence or self-belief about him in moments like this that makes people feel almost sorry for him rather than look up to him.

Perhaps his back isn't to the wall enough. There have been a few occasions when he has lit up, and always when he was on the brink of losing and knew it.

His radio interview on the last Sunday of the divorce referendum campaign was a turning point in that debate, and almost certainly saved his government from defeat.

In the last election, when all hope was more or less lost, he hammered Ahern in debate on television, and incidentally showed himself to be comfortable with the kind of social democratic values that could generate a much larger following if they were articulated and substantiated more often.

And as Taoiseach he showed that he wouldn't let anybody use him as a doormat and especially not John Major and Gerry Adams.

So maybe he needs to be pressed more. Maybe his deputies should demand that he occupy a more central role, and start delivering the kind of sustained energy and passion of which he's capable. Maybe he needs to occupy a more authoritative role in his party, and insist that all the major stuff comes to him (even if he's on a day off).

For instance, Fine Gael made a major tactical error in the recent controversy about David Andrews's handling of promotions. They had all the stuff to seriously embarrass the Government in the Dail, but instead of giving it to the party leader to let him put Andrews under pressure in the House, they gave it to Charlie Bird of RTE the night before. Andrews, thus forewarned by the television news, sailed through what should have been a dark hour.

On the other hand, on an issue where people do expect John Bruton to speak forcefully for them, the situation regarding the killers of Det Garda Jerry McCabe, he was not to be seen on the news at all. Others in his party handled it, and as a result it was Des O'Malley who ended up speaking for us all.

In addition to taking more control of who says what and when, maybe John Bruton needs to get out into the street more, not for clumsy photo opportunities, but to listen and learn. People have no doubt about John Bruton that he's on Ireland's side, but they know that Ahern is on their side. A transparent empathy with people's lives is one of Ahern's great strengths. John Bruton has it (he wouldn't still be in politics otherwise) but it's far less transparent.

Bruton could go down in history as the only Taoiseach we ever had (albeit a good one) who was never elected by the vote of the people of Ireland. He has one more opportunity to put that right. It could happen by default, given the mounting difficulties this Government faces. But, otherwise, it won't happen without a fundamental change in his persona.

He doesn't have to become what he isn't. But he does have to show us much more what he's really made of.