On comparing
Historical comparisons in politics and political journalism are usually not drawn to make something better understood in any rational sense.
They are usually drawn to make imminent political action appear more legitimate to the public, or to make events understandable psychologically. That’s what the comparison of the bomb attacks on the US with Pearl Harbour is supposed to achieve, and that’s what a comparison of Ossama Bin Laden with Hitler is supposed to achieve.
Take them for that, but don’t take them any further.