The Globe and Mail reports in its Thursday edition that Canada's plans for high-speed rail in the Toronto-Quebec City corridor finally got the green light from the feds on Tuesday. Guest columnists David Jones and Tasnim Fariha write, however, that major infrastructure projects in Canada -- particularly public-private partnerships, a category to which the high-speed rail belongs -- are often subject to drift, delays and uncertainty. Smaller-scale rail projects hold myriad examples. Toronto's Eglinton light rail is estimated to be $1.8-billion over budget; the Hazel McCallion LRT in the Toronto area, $4.4-billion; the Surrey-Langley Skytrain in the Vancouver area, $2-billion. All have faced delays, with the Eglinton LRT still not operational after 13 years. Moreover, with Parliament prorogued and political attention flitting elsewhere, Alto, as Ottawa has called the project, risks falling between the cracks. Against these challenges, high-speed rail must be seen as a nation-building project, particularly in the face of economically harmful tariffs and 51st-state threats. Ottawa must learn the lessons of the past so that mistakes are not repeated and, above all, keep this project insulated from politics.