Your reasoning, as well as your simile, is flawed.
First let us address the former. You reason away the peril of dispensing with the due process rights, demanded by the 4th Amendment of the US Constituion, by suggesting that this infringement is both justified and confined to what is considered a terrorist by today's definition. While it might well be justified, such justnification, if it is to be applied to a US citizen, demands proof being presented in a court of law and an apt sentence being handed down by that court prior to the execution of the sentence. That is the law of this land, Ody, and there is no Constitutional caveat excluding the crime of terror within the law. Once we permit our president to act as judge and jury in the procecution of even the evilest and most dangerous of our fellow citizens, then there is absolutely no check that protects any citizen should his or her actions be perceived as evil or dangerous by a future president who chooses draconian measures with this president's actions as precident. Surely you understand how subjective the definition of "terrorist" is, no? Which brings me to your WWII comparison.
The situation surrounding German-Americans siding with the axis powers of that war and being killed on the battlefIeld by their fellow citizens who fought for the allies in Europe is a very different situation since those Americans of hun blood perished upon a battlefield. In the case of those targeted by our drones, those men were not engaged upon a battlefield when they were assassinated by Obama. No proof of their crimes was presented to any court. Did they deserve to die? Quite possisbly, but are we so sure of their guilt that the violation of their 4th Amendment rights was warranted? I know that I can't be that sure. We have now learned that there were four US citizens dispensed with in this manner. Four Americans killed at the direction of the leader of the free world. Say that sentence out loud a few times and listen to what it sounds like. It sounds to me like America is in trouble and the free world is in danger at the hands of its leader.
This very message board is populated with Americans who are at odds with their government and especially their president. What if other dangerous Liberals take the presidency in the next few cycles and one of them decides that our dissent poses a clearmand present danger to America and some of us receive the label of "Terrorists". What will keep drones from seeking us out wherever we are and blowing us to smithereens? Never gonna happen, you say. Really? Never?
I'm afraid that I don't share your confidence in that regard. Sadly, four dead Americans testify that a Rubicon has already been crossed and Senator Paul's performance only amounted to an exercise in pointing out a wrong rather than righting it.
You are a very intelligent man, Ody. I honestly hope that you will see the danger this new paradigm poses to the very liberty that you and your fellow soldiers serve to defend. This poison must be put back in the bottle while we still have a chance to recant it; before it becomes just one more weapon that kills the grand experiment that is America.