The letter wasn't aimed just at veterans, but at anyone thinking they might vote Liberal; a message embedded in a single line from Matt Luloff, a former soldier who has also worked for Liberal MPs — "I'm a Liberal because of policy like this."
It's an example of the new reality of federal election campaigning: in the micro-targeting of policies is the macro-targeting of ideologies.
Both veterans care and child care have become stand-in issues in the election, political scientists say, resulting in parties waging the ideological debates of campaigns past in a different way.
"Veterans issues have become an issue in and of itself, but the actual affected community is very small," said Cristine de Clercy, an associate professor of political science at the University of Western Ontario. There are about 700,000 veterans in the country, but likely no single riding where they could swing a vote.
"But what veterans are a proxy for is several other big ideas about what does Canada stand for, what should our orientation be vis-a-vis our role in the international community," she said.
For the Liberals in particular, talking about veterans is a way into talking about issues the Conservatives usually perceive as their strength — foreign policy and defence, said Elizabeth Goodyear-Grant, an associate professor of political science at Queens University in Kingston, Ont.
The Conservatives have relentlessly attacked Trudeau for his past comments on the ongoing war in Syria and Iraq but talking about veterans allows the Liberals to turn the tables, by focusing on the Conservatives' treatment of former soldiers, she said.
"If you really care about foreign politics and security, why are you doing this to the Canadians who have served?" Goodyear-Grant said of the Liberals' underlying message.
On child care, an issue broadly understood as the parties' pitches to families, the debate is actually about the role of the state.
The New Democrats propose a national day-care plan, the Conservatives stick with their increased benefits program and child-care cheques and the Liberals come up the middle pledging to rejig those benefits so that only those who truly need the money benefit.
So it becomes a question of how people view the role of the state and whether big programs or small ones are better. Not only families with children are thinking about that, said de Clercy.
"People who don't have children might still consider it again as a proxy for how is this party going to handle the question of taking care of the most vulnerable people in our society, the needs of working parents and working- class and middle-class people, these sorts of issues."
Twenty years ago, parties couldn't run these kinds of campaigns because they didn't have the detailed knowledge of who the voters are, how they'd vote, particular demographics of particular ridings — all information available now that helps shape messaging, strategy and platform development in an era of tighter electioneering rules and relatively limited financing.
So broad-based debates on broad issues such as free trade or the Constitution once were the only choice. That's changed and with it, a change in how people connect, said Goodyear-Grant.
"People don't experience the same campaigns because they are sort of focused on certain niche issues, 'I'm a veteran and Trudeau is promising this for veterans and my vote is decided,'" she said.
"They tune out."
Erin Tolley, an assistant professor of political science at the University of Toronto, takes a different view. Without the big ideological debates, people are focused on what each party will do for them.
"People are now actually talking about what would you do and what do your policies mean for me as a voter and how is your policy going to affect my life," she said.
"It's kind of a good thing that we're actually talking about what each party would do."
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