Consider what could happen if Congress reforms the corporate tax code to disallow the deductibility of interest expenses, as Republican tax writers have proposed.
That could lead, over time, to a more efficient economy that encourages investment and discourages debt as hoped, but it could also have some pretty serious unintended consequences:
“If interest expense is no longer deductible, it is questionable whether banking is a viable industry,” according to economists Michael Feroli and Jesse Edgerton of J.P. Morgan Chase.

And no one knows what will happen if Dodd-Frank is repealed.
The last time we deregulated banks, it did not end well.