do tariffs help us to maintain a favorable balance of trade and balance of payments.
http://economics.about.com/cs/taxpolicy/a/tariffs.htm
http://en.wikipedia.org/wiki/Tariff#Economic_analysis
Read and decide. Often, what a tax or tariff is intended to do doesn't really work. You'd need to be more specific in your question and possibly the period of time you're dealing with.
Right now, for example, no tariffs could do more to make the American public try to avoide "made in China" than China is doing to itself, but that hasn't always been the case.
It's somewhat relative. Read and think. If these two articles don't give you enough information, go to http://www.google.com and enter tariffs or other search terms and see what results you get.
=)