There are many examples of tariffs in the world. In US history, at least, the two most famous tariffs were the Smoot-Hawley Tariff of 1930 and the “Tariff of Abominations” from 1828.
It is hard to know exactly what you are looking for when you ask about the “implications” of tariffs. There are any number of things that could be seen as the implication of a tariff. One implication of a tariff is that countries have the right to control what, in the way of goods, comes into their borders. This is because countries are sovereign and cannot be told what to do by any higher authority unless the country itself gives that body the power to do so. Economically speaking, the implication of a tariff is that it will tend to protect domestic industries from foreign competition. Tariffs make imported goods more expensive. This allows domestic goods to have a better chance to compete. This is why many people want more tariffs—they think tariffs will allow more jobs to be created within their country.
So, we can say that tariffs protect domestic industries and that they show that countries are sovereign. These are two implications of tariffs.