But he does not need to persuade the British, Australians or US President Barack Obama that he is an honest broker and a fair-minded leader: all he has to do is persuade Malaysians that he is what he says.
And a good way to begin is by engaging Malaysians at home and by using arguments based on factual assumptions rather than go halfway across the globe and speak in London.
For example, saying that the Catholic weekly, Herald, is widely circulated just shows either how misinformed Najib is or how much he cares about facts.
For the record, the Herald publishes only 14,000 copies for about a million Catholics in a country of 29 million people. It is more likely sold out before more people can get their hands on a copy.
And national peace, harmony and security cannot be at the expense of any minority. Najib is right to say that the majority should not be marginalised but that holds true for the minority as well.
It is the same with calling for moderation and dialogue between Sunni and Shia Muslims worldwide but allowing religious authorities back home to restrict Shia Islam ostensibly because Malay Muslims have been following the Sunni branch since time immemorial.
One cannot say one thing abroad but keep silent at home about what is happening.
The Federal Constitution confers the right to practise one's faith freely but does not allow other faiths to proselytize to Muslims.
But what about Muslims and Muslims? And should it not be left to the state rulers to decide this rather than the religious authorities?
Perhaps it is time for the Najib administration to really know its constituency before relying on advisers and experts who might have their own agendas rather than what the prime minister envisions for Malaysia.
It also appears that the lessons of GE13 have not been learnt: the PM and his team of advisors still believe that giving interviews to Reuters and CNN and "building his brand" is still the way to go.
He might appear to be a moderate and progressive leader on the global stage but his words ring hollow at home.
His countrymen need him to say the same things at home, to silence the extremists, to assure the minorities, and to lead a government to serve the people.
Only then is his mandate fulfilled, not on the world stage but at home. After all, it is Malaysians who voted for him and his party, not the journalists in Reuters or CNN or the politicians in London, Washington or Canberra. – November 1, 2013.