Trump is skipping Davos to deal with the partial government shutdown as Democrats refuse to approve funding for the US$5.7 billion wall he wants to build along the Mexican border.
Mnangagwa is preoccupied with violent protests over rising fuel costs in Zimbabwe that left at least a dozen people dead last week.
Modi is busy preparing for a tough general election in India this spring as he faces a resurgent Congress Party, the main opposition to his governing BJP.
Trudeau is also staying away after coming under fire from critics in Canada over the cost of his Davos sojourn last year, reported to be at least NZ$760,000.
Macron said "non" to avoid further angering "yellow-vest" protesters who have taken to the streets of France for 10 consecutive weekends.
Instead, he mounted a charm offensive for 150 international business leaders in the gilded splendour of the Palace of Versailles.
However, the "yellow vests" managed to intrude on his attempt to convince foreign investors not to be put off by the protests, with demonstrators gathering outside holding placards complaining of low wages.
Macron's disastrous approval ratings and the continuing mayhem on French streets mark a stark contrast with last January, when he triumphantly took the spotlight in Davos.
"France is back!" he proclaimed to fellow world leaders and heavyweights of international finance and industry. "France is reconciled with globalisation, the economy and success."
Nothing could now seem further from the truth as the protests over high taxes and the cost of living amplify a populist backlash against big business and the metropolitan elite in the "forgotten France" of struggling rural areas and small towns.
The "yellow-vest" protests have put wind in the sails of Marine Le Pen's far-Right National Rally, while the centrist president is left to make the difficult case that his structural reforms may cause short-term pain but will create jobs and improve living standards in the future.
About 120 senior figures from multinationals and another 30 business leaders attended Macron's second "Choose France" conference in the Versailles palace built for Louis XIV, the Sun King.
Among them were Satya Nadella, Microsoft's chief executive officer, JP Morgan's Jamie Dimon, James Quincy of Coca-Cola and Ikea's boss, Jesper Brodin. Many were stopping off on the way to Davos.
"Yellow vests" lambasted "King Macron" for entertaining foreign capitalists. "A lot of these companies don't even pay tax in France," said Jean-Paul Brossart, 46, a technician.
The meeting began with lunch with Edouard Philippe, the prime minister, followed by what was dubbed a "speed dating" session, with business leaders being offered one-on-one encounters with French ministers.
However, investments announced at the "Choose France" meeting amounted to about 600 million euros, far below last year's 3.5 billion.
