They almost succeeded.
And not on a handful of minor issues; the nominees walked away from the president-elect on some of his most alarming foreign policy positions. Examples:
Trump has talked up the prospects for a strategic partnership with Vladimir Putin's Russia, mainly to fight terrorism in the Middle East. But his nominees for secretary of State and Defense said that's not likely to succeed.
“We’re not likely to ever be friends,” former Exxon CEO
In his campaign, Trump derided the North Atlantic Treaty Organization as obsolete and said he might not defend its members if they don't increase military spending.
Tillerson and retired Marine Gen.
Trump promised to tear up President Obama's nuclear arms deal with Iran; Mattis said the deal was "imperfect," but should be left in place.
Trump called global warming a Chinese hoax and said he'd withdraw from last year's Paris climate agreement; Tillerson dissented from both propositions.
Trump said he would allow — indeed, encourage — U.S. interrogators to use torture on suspected terrorists; his nominee as CIA director, Rep. Mike Pompeo, said he would refuse to carry out any such order.
There was more, but you get the point.
Compared with Trump's freewheeling campaign persona, his nominees were soothing and sensible. They wouldn't have been Hillary Clinton's choices, but they could have been Mitt Romney's.
Even some Democrats were pleased.
"I'm puzzled because many of them sound reasonable," said Sen. Dick Durbin of Illinois, the Senate's second-ranking Democrat. "Far more reasonable than their president."
Democratic firebrand Elizabeth Warren of Massachusetts found herself praising Mattis, a hawkish Marine who was dubbed "Mad Dog" for his ferocity in battle.
"We're counting on you," she said.
Trump pronounced himself delighted.
"All of my Cabinet nominee are looking good and doing a great job," he tweeted on Friday. "I want them to be themselves and express their own thoughts, not mine!"
That's an unusual management doctrine for any chief executive. Previous presidents often said they encouraged robust debate inside the White House — but in front of Congress and the public, they wanted their cabinet secretaries to toe a single, clearly chalked official line.
In Trump's case, though, there is no such line, which is one reason his nominees were allowed to give their thoughts free rein, a person involved in the process told me.
In 2001, George W. Bush's transition team produced a 450-page binder of policy positions to guide his nominees. The Trump team has no comparable manifesto. And Trump's campaign positions aren't always a reliable index to his thinking; he's changed course on several issues already.
In effect, Trump's nominees are behaving as if the president's views on foreign policy are still unformed and up for grabs — as if an appointment to Trump's cabinet is an invitation to join a battle for his ear.
As in any administration, that there will be rival factions. Judging from the confirmation hearings, Tillerson and Mattis may strike an alliance to try to curb their boss' impetuous side.
We haven't heard as much from Trump's closest — and more radical — foreign policy advisers, Michael T. Flynn and Stephen K. Bannon; they don't require confirmation by the Senate. But they've both been more skeptical about NATO and more enthusiastic about Russia.
The result is likely to be a noisy first year as the new team hashes out exactly what President Trump wants to do.
And that's the problem with the Reassurance Offensive: It's only a set of opening bids. It doesn't tell us where Trump will land. Cabinet officers often get overruled; just ask John Kerry.
"At the end of the day, each one of them is going to pursue a Trump agenda and a Trump vision," Trump spokesman Sean Spicer said last week.
Still, it's good to know that when Trump makes big foreign policy decisions, he will have at least a few cautious advisors in the room. Assuming he lets them into the room, that is. And boy, will their memoirs be worth reading.