Canada

They know it’s not feasible in Canada our cities are not dense enough.

This is false. The corridor has a density comparable to other countries with high speed networks.

The Quebec City–Windsor Corridor is the most densely populated and heavily industrialized region of Canada. As its name suggests, the 1,150 km-long region extends from Quebec City in the northeast to Windsor, Ontario in the southwest. With more than 18 million people, it contains about half of the country's population and seven of Canada's 12 largest metropolitan areas, 3 of which are in the top 4. Its relative importance to Canada's economic and political infrastructure renders it akin to the Northeast megalopolis in the United States.

FFS, Sweden has a rail network with trains going at 200 km/h and is currently building sections where trains can go up to 250 km/h, but somehow it's impossible in Canada because we're not dense enough?! Somehow we can expropriate people in a few months and build entire expressway sections, all over the country, sometimes in complete fields, with bridges, but linking a few cities with trains is impossible?! This is just car dependency propaganda.

EDIT: This fucking country was founded on railways. The west wouldn't be as populated as it is without these. Today we're talking about establishing a high speed line over a fraction of that distance, linking multiple major cities with millions of people, and we don't have the density? What a fucking joke.