One of the triggering factors before the Boston Tea Party was the increased number of tariffs levied by the British on the American colonies which caused the Sons of Liberties to throw tea into the Boston Harbor.
The politician wanted to collect more taxes on items that were imported from other countries, so he proposed a tariff at the debate.
The political situation in Zimbabwe caused the shipping tariff to increase, cutting into company profits and making further shipments to that country too costly to maintain.