Story highlights Sen. John McCain and Donald Trump have had a tense relationship for years

McCain questioned Trump's handling of US-Australia relations and a recent raid in Yemen

Washington (CNN) John McCain seems to be relishing a new role in the Senate: one of President Donald Trump's leading trolls, going where fellow Republican senators dare not go in public.

The Arizona senator has publicly criticized the President over his handling of US relations with Australia, his Cabinet picks and his highly contentious travel and immigration ban -- and that's just this week.

Following his re-election last fall, McCain is back to his "maverick" style.

"I'm the one that said Ronald Reagan shouldn't send Marines to Afghanistan, I'm the one that said Donald Rumsfeld should be fired, I've said the general in Afghanistan should be fired," McCain said Thursday, when asked by CNN about his public opposition to Trump. "Look, I have done what I have done right for this country under Republican and Democrat presidents. I will continue to do so. This is not a departure from the way I've conducted myself in the United States Senate."

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When CNN asked if he felt like he had more standing than other lawmakers to criticize the president, he deflected with a self-effacing joke.