Unlike his ardent followers, it is not easy for policymakers and foreign countries to make sense of U.S. President Donald Trump. One person they all turn to these days is Jared Kushner, the 36-year-old son-in-law of the President. Mr. Kushner has emerged as the most powerful influence on the most powerful office on the planet. Mr. Kushner is married to the President’s favourite daughter, Ivanka Trump.

What is his reach?

Mr. Kushner’s prominence in the administration is rising. For instance, he set the ambience and agenda for Mr. Trump’s meeting with Chinese President Xi Jinping — one bilateral relationship that could define the 45th presidency.

Then again, the Chairman of the Joint Chiefs of Staff Joseph Dunford invited him to join him on a tour of Iraq. Mr. Kushner has a finger in every pie. He is involved in the White House policy on China, Mexico, West Asia and Canada. He strategises on combating the Islamic State.

He heads the newly created Office of American Innovation, which has the mandate to implement highly effective private sector practices in government. Mr. Kushner is a senior adviser to Mr. Trump. The President apparently even believes that his son-in-law, an orthodox Jew, could broker peace between Israel and Arabs.

How is he helping?

The son-in-law has been instrumental in blunting the edge of Mr. Trump’s diatribe against China and Mexico, two close trade partners of the U.S. Mr. Trump had sought to make U.S. relations with Taiwan a bargaining chip with China, a move that pushed bilateral ties to a crisis. A telephone conversation between Mr. Xi and Mr. Trump, organised by Mr. Kushner and Chinese Ambassador to the U.S. Cui Tiankai, broke the ice and both leaders met this week in Mar-a-Lago, a private club owned by the President in Florida. The Trump administration’s draft plan to renegotiate the North Atlantic Free Trade Agreement with Mexico and Canada is far tempered and conventional than Mr. Trump’s campaign rhetoric against it.

Is he qualified for the job?

With no political or governmental experience, Mr. Kushner managed to wield enormous influence in Mr. Trump’s presidential campaign.

His veto power on all matters Trump first came to light when New Jersey Governor Chris Christie, the first traditional Republican to endorse the insurgent, was edged out of the inner circle and finally sent to the wilderness.

Since then, anyone who wanted to break into the sanctorum of the Trump Towers and later the White House, knew whom to propitiate. Going by recent developments, the Chinese have done that job the best.

Is there conflict of interest?

Mr. Kushner waded into the first conflict of interest controversy, as a Chinese group with links to the Communist Party emerged as a potential investor in a bleeding property in Manhattan that he had bought for $1.8 billion in 2007, and later divested from.

As the issue flared up, negotiations were called off last month. But Kushner Cos, the real estate business he inherited and is now managed by a trust of which he is the prime beneficiary, owns or manages 20,000 apartments and 13 million sq. ft. of office space in New York, New Jersey, Maryland and Illinois. Mr. Kushner has liquidated his stake in 58 businesses while moving to the administration, but he and wife Ivanka Trump could be worth $740 million, according to disclosures by the White House recently. It is unlikely that his first conflict of interest controversy will be his last.

People who know him are not convinced that his record or acumen justifies his prominence. Elizabeth Spiers, founding editor of Gawker and former editor-in-chief of the New York Observer, a paper once owned by Mr. Kushner, wrote in a Washington Post piece: “...and my experience doesn’t bode well for the Office of American Innovation. Not everything that works in the private sector is transferable to the public sector — and even if it were, Kushner isn’t the best person to transfer it.” She added: “When I worked for him, I didn’t think he had a realistic view of his own capabilities since, like his father-in-law, he seemed to view his wealth and its concomitant accoutrements as rewards for his personal success in business, and not something he would have had in any case.”