The main reason for a lot of Australians saying no, he does not need to apologize, is simply: why should someone say sorry for something they were not directly responsible for? White people' of today were not responsible for the decisions and the actions taken in the past when most people weren't even born yet. So what do they have to be sorry for?
It's like someone coming up to you and apologizing for abusing your sister, instead of the actual person who did it. Does it make you feel better to know that somebody else, who you know wasn't responsible was "compassionate" enough to apologize? Probably not. Really it should make no difference to the Aborigines whether or not John Howard does apologize.
The government has already released a statement of regret, which after being read it should be assumed that we are "sorry" for what has happened. John Howard in fact motioned a statement of "deep and sincere regret over the removal of Aboriginal children from their parents". He also said: "the treatment of indigenous Australians represents the most blemished chapter in the history of this country."
So he feels bad, he agrees it was wrong, i.e. he's sorry. What more can a man do? Should he be expected to say, "oh I'm sorry that someone else did that to you but you I'll take the blame anyway", or I'm sorry that I'm white like the people who ruined your lives so I'll take responsibility".
In that case what about mixed aboriginals, wouldn't they also be expected to apologize, after all they have white blood in them and they should be held responsible for their ancestors' actions as well. But I doubt they would be expected to apologize. Wasn't a voicing of regret enough to prove that John...