The Globe and Mail reports in its Thursday edition that with President Donald Trump threatening tariffs to help balance the U.S. budget, the key challenge for Canada is clear: to design a package of retaliatory tariffs and countermeasures that maximally affect U.S. economic interests. Guest columnist Tae Hoon Oum writes that one effective strategy is targeting the U.S.'s massive service trade surplus. The U.S. enjoys a substantial services trade surplus with Canada, China and Europe. Notably, these services are dominated by world-class U.S. companies such as Microsoft, Google, Meta, Amazon, Tesla, major banks, insurers, universities, health care providers, film studios and publishers. These services can take many forms. Worldwide, U.S. services exports amounted to $926-billion (U.S.) with a surplus of $245.7-billion (U.S.). The actual economic footprint of U.S. services exports is much larger than these figures suggest. Targeting U.S. commercial services through retaliatory tariffs is a promising strategy because these are industries where the U.S. holds a dominant position in the global economy. By shifting the focus to U.S. service trade surpluses, Canada and its allies could fundamentally alter the trade narrative.