Washington: When Trump goes low, the Obamas go high – and Hillary Clinton lies low.

It was a clever rallying call by Michelle Obama as this campaign descended into the gutter – "when they go low, we go high!". But perhaps just as clever is Clinton's interpretation of the "low" bit – she has withdrawn to the shadows, is doing fewer public appearances and is leaving Donald Trump at stage centre, where he consumes himself in his fury, his conspiracy theories and his denials that don't amount to much.

On Friday there was more to deny, as the women of America fleshed out what they know of the GOP candidate. And because Trump can't help himself, his counter-attacks ensure that the story of his hands, his "big" wandering hands, remains at the centre of discourse that nominally is about who should be the most powerful individual in the world.

But the Obamas have become the frontline force of the Clinton campaign – Michelle first, with a Thursday one-punch excoriation of Trump on his treatment of women that went viral; and on Friday, a two-punch hammer blow by Barack that shredded Trump's pretensions to high office.