Global worries hit stocks; breaking up the banks; risks from low oil prices

It's another down day for stocks(^DJI, ^GSPC, ^IXIC), as oil and a big selloff in Japan weigh on U.S. equities.

To discuss some of the big stories of the day are Yahoo Finance's Alexis Christoforous, Yahoo Finance Columnist Rick Newman, Bobbi Rebell, television and multimedia reporter at Reuters, andBloomberg Intelligence US Chief Economist, Carl Riccadonna.