President Donald Trump is threatening to primary Republicans who vote against his trade agenda.The warning comes after six Republicans joined Democrats on Wednesday to effectively repeal Trumps tariffs on Canada.Reps. Thomas Mas sie of Kentucky, Don Bacon of Nebraska and Kevin Kiley of California were among those who broke ranks."TARIFFS have given us Great National Security because the mere mention of the word has Countries agreeing to our strongest wishes. TARIFFS have given us Economic and National Security, and no Republican should be responsible for destroying this privilege," Trump wrote.RELATED STORY | New analysis shows Trump's tariffs cost US households an average of $1,000 last yearDemocrats have gained the ability to force more tariff votes in the coming weeks.Even if the Senate passes the measure, Trump could still veto it.The effective tariff rate on Canadian goods was 0.1 percent prior to Trumps administration; it now stands at 3.9 percent.RELATED STORY | Trump flips on Canada-China accord, proposes 100% tariff in turnaroundSince Trump took office, trade with both nations has declined, the data show.Last month, Trump threatened to impose a 100% tariff on Canadian goods if Canada followed through with a planned trade deal with China. Trump suggested Canada would become a drop-off port for Chinese goods entering the United States. He referred to Canadian Prime Minister Mark Carney as Governor Carney, indicating he has not fully given up on his pursuit of making Canada Americas 51st state. ...read more read less