French President Francois Hollande walked arm-in-arm with German Chancellor Angela Merkel and Mali's President Ibrahim Boubacar Keita. Israeli Prime Minister Benjamin Netanyahu and Palestinian leader Mahmoud Abbas, in a powerful act of unity, were also links in the chain of high-profile figures as they led the sombre procession. About 40 world leaders were there.
Why didn't Obama go? It's a question, and a headache, the White House is now dealing with in the aftermath of what turned out to be a stunning display by millions of people in Paris and across the country who wanted to honour the 17 victims of three days of bloodshed in France. On Sunday and Monday morning, the U.S. news shows had their reporters and commentators weighing in on the absence of a high-profile American at the rally.
If Obama couldn't go, why didn't the White House make sure the U.S. was represented by Vice-President Joe Biden, or Secretary of State John Kerry, or Attorney General Eric Holder who was actually in Paris for meetings?
"The White House's explanation is pathetic," CNN host Fareed Zakaria said. "It's possible that you couldn't send Obama there — I thought this is why God invented vice-presidents."
He said the White House made a mistake when it judged that U.S. ambassador to France Jane Hartley's presence would be enough. She was one of the highest-level officials to attend, along with the assistant secretary of state for European affairs Victoria Nuland.
The White House's explanation is that the U.S. was represented by Hartley and by Holder, who was in meetings, not at the march, and one official also noted the security concerns of Obama or Biden attending such a gathering.
"It is worth noting that the security requirements for both the president and (vice-president) can be distracting from events like this — for once this event is not about us," an official, who would not speak on the record, told CNN on Sunday night.
Kerry will visit Paris this week
Administration officials are also pointing to what Obama has done to show solidarity with France since the deadly attacks in Paris, including his visit to the French embassy in Washington where he signed a book of condolences, his personal phone call to Hollande, his written statement and public comments on two separate days last week.
U.S. security, intelligence and terrorism officials have been working with their French counterparts and the administration is extremely engaged in the developments out of France, White House officials say.
Secretary of State John Kerry didn't go to Paris on Sunday because of a pre-planned trip to India which is where he is spending most of Monday. He will go to the French capital later in the week.
He told reporters in India that he very much wanted to be in Paris on Sunday and he tried to downplay any controversy that Obama's or his absence is generating.
"This is sort of quibbling a little bit in the sense that our assistant Secretary of State Victoria Nuland was there and marched, our ambassador was there and marched, many people from the embassy were there and marched.
The White House's defence of how it is handling the Paris attacks and its judgment call on who would attend the unity march won't stop the questions from being raised, however, or the criticism, which is mostly coming from home, not from France.
The U.S. ambassador to France told CNN on Monday morning that Hollande personally thanked her on Sunday when she saw him, for the U.S.'s support and cooperation, and that all the officials she has been in touch with have expressed nothing but gratitude.
"If you talk to the French they think we have been unbelievably supportive," she said.