There’s concerns Donald Trump's change of tune since his assassination attempt may not last long. 

Trump will formally accept the Republication nomination about 2pm today, the first time he's spoken since surviving the attack. 

FSN correspondent Simon Marks says since the Republican National Convention started this week, they've been suggesting it's time for American voters to rethink their definition of the party. 

He told Mike Hosking Trump's been strongly campaigning for unity but wonders whether this is a real change of behaviour, or if it's a one-night wonder. 

LISTEN ABOVE