Hannah Thomas-Peter, US Correspondent

Let the UNGA games begin, as one mischievous diplomat - who shall remain nameless - put it.

Yes, it's September in New York, which means that after fashion week, sure as night follows day, comes the United Nations General Assembly.

Thousands of diplomats and heads of state will descend on this little island for their own version of the front row.

But instead of towering heels and Instagram there'll be high-level meetings, encounters, brush pasts, pool sprays and all sorts of other things no one outside these rarified circles understands.


Image: The General Assembly's annual meeting has a maddeningly broad and vague remit

This year the theme of the assembly is maddeningly, and entirely typically, simultaneously broad, vague and noble: "striving for peace and a decent life for all on a sustainable planet".

Unfortunately, the leader of the free world is likely to make the pursuit of those goals, for this week at least, rather difficult.

It's Donald Trump's first UNGA games, and the diplomats are holding their breath to see what might happen.

Firstly Trump doesn't like the UN. He thinks it's ineffective and expensive. He might be right.

The problem is he will probably say that out loud, at the only big meeting he's due to attend, which focuses on reforming the UN.

It's Donald Trump's first UNGA games, and the diplomats are holding their breath to see what might happen.

This will be awkward at best.

He is also going to have to address the General Assembly at a time when the world is looking for American leadership on all sorts of issues, from the escalating nuclear crisis in North Korea to Syria.

But he is known for veering off script, or undermining a crafted message with a tweet or throwaway comment.

In such a choreographed forum, on such a global stage, these things could have even more serious repercussions and be even more distracting than they normally are.

And then there's the practical, physical issue of state-craft.

Trump seems to go out of his way to engineer torturous, headline-grabbing handshakes, has a breathtaking lack of regard for convention and decorum, and possesses the sort of cartoonish gaucheness that sometimes defies belief.

Image: The President could be outshone by another 'new boy' - France's Emmanuel Macron

He once actually elbowed a counterpart out of the way to make sure he had the best position as the cameras rolled.

And he may well be outshone at times by other stars like French President Emmanuel Macron and Canada's Justin Trudeau.

Trump hates sharing the spotlight. Ask Steve Bannon.

It will be fascinating to observe someone with a showman's relish for the big moment navigate the fraught terrain of an event run by an international organisation he has railed against for "weakness" and "incompetence".

And how to balance the need for genuine partners against ISIS, on Iran and other pressing issues of our time, when he was elected on the principle of America first and has made a point of dismantling the ties (like trade and climate agreements) that bind countries across the world?

Taking all this in to account, I think the President's diplomatic debut could be just as interesting as the biggest fashion week shows.

Just don't expect it to be elegant, or pretty.

Sky Views is a series of comment pieces by Sky News editors and correspondents, published every morning.

Previously on Sky Views: Adam Boulton - The UK's costly brain drain