A decisive win, but as the party membership is not really representative of the UK voting public, being about 75 per cent male, and certainly nowhere near the same diversity, voter opinion of Johnson is at best 50:50, supporters vs detractors.

It will be of considerable concern for many that Johnson has the overt support of Donald Trump - indeed, perhaps not surprisingly, Trump was almost taking credit in his supportive comments.

It is no understatement to say that Boris is very hard to read, and therefore to attempt to predict how he will perform. He will be tested almost immediately on three major issues, Brexit, the UK economy, and Iran.

Although Johnson has promised to "unite the party" this seems most unlikely, especially as there is a significant "rump" in his party that will not accept a "hard Brexit". Given the continued refusal of the Europeans to renegotiate the deal they had reached with Theresa May, and given the intransigence of many in the House of Commons, on both sides of the House, it is hard to see how simply changing the "jockey" from May to Johnson, will make any practical difference, especially when many feel that the "horse is crook".

A leading member of the House of Lords, Lord Robert Hayward, drew two parallels in being asked to comment on Johnson. First, he compared him to Nick Kyrgios - you never know what you'll get until he gets on court!

Second, he compared him to Ronald Reagan. Having said that, Johnson is a hopeless negotiator, as he doesn't do detail. He would need to be like Reagan and delegate to "good, qualified, people", which would be his best hope of getting a good outcome.

The mind should boggle at the thought of such a complex and unpredictable character!

Theresa May's biggest mistake was to seek an early election, claiming that she would like a 100-seat majority, to put her in a strong position to negotiate Brexit with the Europeans.

Unfortunately, the voter turnout for that election was quite different from what had turned out for Cameron's ill-conceived original referendum, especially with a much stronger youth turnout, such that she ended up with a minority government, and a divided party. As a result May was never able, even after multiple attempts, to garner the essential support of Parliament for her Brexit deal.

With the Conservative Party still divided on the issue, and given Johnson's track record of having written op-eds both for and against leaving, and his Brexit campaign exaggerations of the "cost" of EU membership, and the threat of being flooded with millions of migrants from the Middle East and North Africa, it is hard to see how he can hope to succeed where May failed.

The media has already identified some eight options for Johnson to move forward on Brexit, including a second referendum, even another election. Who knows?

While the recent focus in the UK has been almost exclusively on politics, it will soon shift back to the economy now Johnson has been confirmed as PM, and also because he promised an early budget to boost the economy ahead of any further Brexit negotiations.

It has been widely assumed that the UK economy is on a cliff edge and that Brexit could push it over. However, does it really need a boost, with the unemployment rate still at a 45-year low, average earnings picking up, even though overall growth has been insipid, and house prices falling? Either way, the economy will be a challenge for the new PM and his Chancellor.

The situation with Iran has been escalating in a somewhat unwieldy manner, with ships being seized by both sides, against a volatile Trump strategy, initially almost seeking a military confrontation, then backing off, but generally encouraging Israel.

Boris will be under some pressure to join his "mate" Trump's anti-Iran coalition, while the Europeans have been developing mechanisms to continue to trade with Iran, without breaching the agreed sanctions. Johnson's stint as UK foreign minister doesn't instill much confidence in how he will handle this, his first foreign policy challenge.

Watch this space, and hang on!

John Hewson is a professor at the Crawford School of Public Policy, ANU, and a former Liberal opposition leader.