Industry Minister Christian Paradis' April 10 letter to Canada's first astronaut was full of praise for Garneau's efforts to persuade officials to install the space arm at Ottawa's aviation museum.
The missive, in French and hand-addressed to "Marc," was also copied to James Moore, then heritage minister and responsible for the museum.
Three weeks later, on May 2, Moore spoke at a splashy event showing off the Canadarm display to journalists and 62 invited VIPs.
But Garneau, the first Canadian in space and a key voice in creating the display, was not among them.
He tweeted even as the ceremony unfolded: "Would really have appreciated invitation from Gov't to attend. No such luck," later accusing the Conservatives of petty partisanship.
As the snub was reported online and over broadcast outlets, an unapologetic Moore stood up in the House of Commons that afternoon and dismissed Liberal MPs' heckling about the incident.
"Members opposite can obsess about their caucus and maybe we will obsess about Canadian history," he said.
Six months earlier, on Nov. 22, Moore had himself written to Garneau thanking him for a letter — hand-addressed to "James" almost four months earlier — urging the display of the Canadarm at the museum.
The letters and other material related to the incident were obtained under the Access to Information Act.
A spokeswoman for Moore said on the day of the snub that the museum — not the minister — was responsible for the guest list, distancing the politicians from the public servants who helped organize the event.
The letters and other previously released records, however, indicate close oversight of the media event by both ministers' offices and by the Privy Council Office, the prime minister's own department.
For more than three months, officials in the ministers' offices and PCO vetted all the planning documents and news releases for the May 2 unveiling.
Garneau received a telephone apology days later from a museum official, who took the blame for the "oversight." Garneau says the woman "took the fall."
"I believe my status as a Liberal MP played a role given the highly partisan nature of the current Conservative government," he said. Four former Canadian astronauts were on the guest list, though they did not attend.
Dozens of emails from ordinary citizens to Moore, also obtained under access to information, show a similar — and universal — contempt for the government's behaviour, even from Conservative party supporters.
"Regardless of whomever made up the guest-list, YOU should have had the courage and thoughtfulness to make sure that Marc Garneau was there," wrote one person the evening of the snub.
That was echoed in another email: "You might not have been responsible for the guest-list but you are in charge of the department, so the responsibility falls on your shoulders."
Another criticized Moore's behaviour in the Commons, saying he "could have proactively expressed regret that Marc Garneau MP had not been invited to the event, rather than attempting to belittle the oversight."
One person wrote: "Marc Garneau deserves an apology, not just a brush off." And another: "I do not believe for one second that the controlling Conservatives had no hand in the list of invitees."
A self-described "strong conservative supporter" called the incident a "humiliation." Another party supporter said: "You have brought disrespect to my conservative party and country with your partisan behaviour."
The list of adjectives and phrases in the more than 60 emails was all negative: childish, despicably partisan, tacky, classless and petty, absolute disgrace, spiteful and mean-spirited, ungracious, nasty, ignorant, sleazy behaviour, loutish behaviour, puerile, boorish discourtesy.
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