OTTAWA—In August 2015, the federal Liberals presented a bold and ambitious fiscal and economic platform. At a time when even the federal NDP was promising balanced budgets, the Liberal plan proposed large deficits for the next two fiscal years to stimulate job creation and reduce poverty. Their argument was that these deficits would pay for significant infrastructure, housing investments, a middle-class income tax cut, large increases in child benefit payments for low- and middle-income parents and enhanced benefits for low-income seniors.