Im sorry if I didin't understand: "If another country has a similar tax, their goods can be imported without extra duties. If they don't, you assess the goods

Im sorry if I didin't understand: "If another country has a similar tax, their goods can be imported without extra duties. If they don't, you assess the goods imported and charge the equivalent duty." The equivalent duty meaning same as carbon taxers or less? (asuming non carbon taxers have less duty)