U.S. banks face a variety of problems: slow economic growth that weakens loan demand, low interest rates that pressure investment returns, tighter regulation that adds to increasing costs, and rising social and political movements against the sector. The industry faces significant headwinds in the near-to mid-term in this new reality. Despite these issues financial sector stocks have risen over 13 percent since the start of the year. Is this rally sustainable? Here are the main topics that investors need to consider.