MONTREAL — Tariffs and economic angst delivered a significant blow to Canadian National Railway Co. last year, as the question mark hanging over North American free trade continues to threaten profits in 2026. “Tariffs, trade uncertainty and volatility impacted our full-year 2025 revenues by over $350 million,” chief commercial officer Janet Drysdale told analysts on a conference call Friday. Forest products and metals took the biggest bruising, she said, with the two segments seeing a year-over-year revenue drop of eight and four per cent, respectively, in the latest quarter. …On top of trade uncertainty, a less publicized source of angst has rippled through the rail industry since last summer. Union Pacific Corp., the second-largest railway operator in the United States, announced in July it wants to buy Norfolk Southern Corp. in a US$85-billion deal that would create that country’s first transcontinental railway, and potentially trigger a final wave of rail mergers across North America.