US President Donald Trump has been running his country like a business. The best thing his international partners can do is treat him like the thin-skinned chief executive he is, says DW's Kate Ferguson.
There are three things to bear in mind when dealing with Donald Trump. The first is that he doesn't distinguish between running a casino and a country. The second is that the only currency he has a vested interest in is his approval rating. The third is that he has only one long-term goal — to be re-elected.
The reason that attempts at diplomacy continue to fail is that the usual rules don't apply to Donald Trump. Unlike most democratically elected leaders, he doesn't feel bound by the principles of propriety or precedent. He doesn't care about children being torn from their parents at the Mexican border, or the consequences of a slowdown in global growth.
The only way he'll believe these things matter is if he can be convinced that they're connected to at least one of the three things he does care about: his business, his image or his chances of re-election.
Let's begin with the principle that underlies Trump's attitude to both business and politics: keep it in the family. Over the years, whether he's been running a chain of casinos or a country, his relatives have rarely been far from his side.
Consider the trajectory of his daughter Ivanka. Twenty years ago, as a precocious fifteen-year-old, she co-hosted Miss Teen USA, a pageant her father had recently acquired. Now she advises him on how to manage the world's most powerful economy.
The second thing that keeps Donald Trump awake at night is wondering how many people are reading about him in the New York Times and how they might be persuaded to watch Fox News instead. You need only scroll through his Tweets on any given day to realize that the most powerful man in the world is powerless in the face of his need for approval.
If you really want to get through to the president, don't bother appealing on behalf of the tired, the poor or even the huddled masses yearning to breathe free. Attack his ego instead.
The city of London has recognized this in its decision to allow a giant orange blimp depicting Trump as a nappy-wearing baby to fly over the city during his visit later this week.
Leo Murray, the activist behind the protest action, described the American president as "a man who lacks the capacity for moral shame," arguing that to get through to Trump, "you have to talk to him in a language he understands: personal insults."
When Donald Trump isn't worrying about falling out with his family, or giant blimps flying over London, he is thinking about his re-election in 2020. It's not that he wants another four years in the White House.
In fact, if there were some way of blaming Hillary Clinton for his inability to run again, he'd be happy to avoid it and return to his game of golf. But the problem is that there is nothing that endorses Trump's binary worldview as effectively as an election, where there are winners and losers, people who back him and those who don't, and states that count and those that don't.
The US president can resist alcohol and cigarettes, but he is addicted to public validation, whether as the host in The Apprentice, or as the occupant of the White House.
To ensure Trump is not re-elected in 2020, other countries must do their bit to persuade the people who previously voted for him not to make the same mistake again.