"Have circumstances really changed that much "

JT's first bill was a tax cut, reducing Government revenues

He then reversed the Increase to OAS eligibility increasing long run liabilities.

He then dramatically increased other program spending.

Nowhere is there any plan to bring that structural deficit under control at any point.

"In any case, the projections are based on the federal government not changing policies which is not realistic."

Trudeau Père lost control of the budget in '75, turning what had been a structural Primary Surplus into a structural Primary Deficit. 82', '83, '84 Canada recorded record back to back deficits peaking at 8.1% of GDP - I struggle to think of a major economy who posted a  deficit of such magnitude outside of a major Financial crisis.

It took major austerity by Mulroney and Martin, plus a booming Global economy to balance Canada's books again - 25 years after TP went off the rails.

History is not on your side