In the halcyon first days of his administration, Trump believed there was no challenge too confounding, no conflict too intractable for his son-in-law to tackle.
"I sort of stole her husband," an effusive Trump told roomful of guests on inauguration eve that included his favored daughter Ivanka. "I have a feeling he is going to do a great job."
MORE NEWS:
Security concerns over Trump's phone use
To drive home the size of these expectations, Trump turned his attention directly to Kushner - the grandson of Holocaust survivors, who still observes the Sabbath - to say: "If you can't produce peace in the Middle East, nobody can, okay?"
In the White House, Kushner became one of several senior advisors to the president. But he took a front row seat alongside chief strategist Steve Bannon and chief of staff Reince Priebus, literally and figuratively.
He is often seen standing beside Trump in the Oval Office or climbing the steps of Marine One but rarely heard beyond the corridors of power in Washington.
In person, Kushner is more polite and self-deprecating than steely and silent.
Beyond resolving the Israeli-Palestinian conflict, Kushner was handed a to-do list that included solving America's opioid epidemic and injecting the nation's bureaucracy with entrepreneurial spirit.
For Trump's critics, that was evidence of unbridled hubris - a sign the president and his aides had no idea how difficult it is to run the White House, America and the world.
Kushner was, after all, not a veteran statesman but the young scion of a media and real estate family.
Although a Harvard graduate, he had little political or administrative experience before the 2016 presidential race, when at times Kushnerappeared to be Trump's de facto campaign manager.
For Trump, the ambitious portfolio was a show of confidence in Kushner's ability, a confidence that had grown steadily since he married Ivanka in 2009.
Donald Trump has said that his son-in-law is "doing a great job for the country." Source: AAP
Explosive allegations
Foreign diplomats were among the first to realise the enormous trust that Trump had bestowed upon his young aide.
Embassies scrambling to build contacts with Trump's new administration were quick to realise Kushner's pivotal role as a trusted ambassador and facilitator - but also a presidential family member who would survive the inevitable White House knife fights.
For Shinzo Abe, Theresa May and Xi Jinping, the path to meeting with Trump ran through Kushner.
Kushner was also seen as more internationalist than Bannon, who fueled Trump's more isolationist instincts on trade and immigration.
But those initial diplomatic contacts may have sowed the seeds for what would be a spectacular fall from grace.
Previously undisclosed contacts with Russian ambassador Sergey Kislyak have raised eyebrows, as well as more recent revelations that Kushner also had contacts with Sergei Gorkov, a banker with ties to Vladimir Putin.
The Washington Post has leveled explosive allegations that Kushner proposed a secret communications link to the Kremlin.
Kushner is said to be tied up in the FBI investigation into possible Trump campaign collusion with Moscow, which US intelligence agencies say tried to sway the November election in the Republican's favor.
Jared Kushner at the Ministry of Defense, in Baghdad, Iraq. Source: AAP
Trump has brushed off the allegations and reaffirmed his trust in Kushner, who he described as "doing a great job for the country."
"I have total confidence in him. He is respected by virtually everyone and is working on programs that will save our country billions of dollars. In addition to that, and perhaps more importantly, he is a very good person," the president told the New York Times.
But the Trump-Kushner relationship is reportedly showing signs of strain, and the strain could become severe if Trump's son-in-law is drawn deeper into a Russia inquiry which the president is seeking to keep at arm's length.
In the meantime, Kushner has offered to talk to Congress about his meetings with Russian officials - through a lawyer.
"I sort of stole her husband," Donald Trump has said of his son-in-law Jared Kushner. Source: AAP
