回复21楼:转口哪里都有，但量绝对不多，因为成本更高。看看美加进出口的东西种类就知道了，能源，矿产，金属，汽车，飞机零配件，农产品等是大头。In 2022, U.S. exports of goods to Canada totaled US$357.3 billion. The top export categories (2-digit HS) in 2022 to Canada were: vehicles (US$53.8 billion); nuclear reactors, boilers, machinery (US$49.7 billion); mineral fuel, oil (US$35.3 billion); electric machinery (US$28.3 billion); and plastics & plastic articles (US$17.7 billion).

2023 US Top Trade Partners: Mexico 475.6 billion, China 427.2 billion,
Canada 421.1 billion