Tariffs aren't taxes. That's why they're called tariffs.
As for banks... The banking system is part and parcel of the government. Sure, banks are a private institution, but because the control a good portion of the money supply as well as handle many transactions between members of society and business, they have a function that government has an interest in maintaining in a reliable state. If a bank gets into financial trouble, the government should handle it as a case of criminal neglect by the bank's officers (a crime), while ensuring that those with accounts get covered and remain stable. That is, a "bailout" isn't a free lunch.
Tariffs are a means to regulate international trade, nothing more.
Okay, whoever they are.