I think it is always a good idea to consider other forms of government and it makes sense that the United States would want to consider various changes in the government and the way that it works. It is always a good idea to stay open to new ideas as a country and to be adaptable and flexible.
No, the United States should not consider a dictator in a time of crisis, because there is no dictator in America that would use that power wisely. Even Dick Cheney said something about needing a personal crisis to turn people towards nationalism. At the same time, liberals would use the power of a crisis to institute big government programs and hurt the economy. Americans have political systems in place already to effectively manage a crisis without handing their political system over to a dictatorship.
In the US, we've established a system of government that is supposed to discourage dictators. Although we are supposed to have a government by, for and of the people, if you look at the House and Senate, they don't truly represent most of us. I'm not in favor of giving more power to the legislative branch and disrupting the system of checks and balances. Good leadership means the branches and their heads work together and not against one another, which is more like what we have going on now, but making one branch that much more powerful than another doesn't seem like the best idea either.
No, the United States should never turn absolute power over to any one individual. In the case of Lucius Cinncinatus, the country and its population got lucky. Emperor Caligula is another Roman example to the contrary, showing what happens when the person given power doesn't possess the right moral fiber. Would we want to risk putting a modern Caligula in power, only with access to nukes?