US political violence: 'Decades of polarisation have fuelled a perfect storm,’ historian says

The man charged with killing one Minnesota lawmaker and wounding another had meticulously planned the shootings and intended to inflict more carnage against those on his hit list, driving to the homes of two other legislators on the night of the attacks, a federal prosecutor said on Monday. We speak to historian Matt Dallek, Professor of Political Management at George Washington University, about the rise of political violence in the United States.