As they ate, the president and Mr. Comey made small talk about the election and the crowd sizes at Mr. Trump’s rallies. The president then turned the conversation to whether Mr. Comey would pledge his loyalty to him.Mr. Comey declined to make that pledge. Instead, Mr. Comey has recounted to others, he told Mr. Trump that he would always be honest with him, but that he was not “reliable” in the conventional political sense.
Trump would have known what Comey's answer would be if he had taken the time to understand the oath taken by FBI officers — and members of the military for that matter. Those oaths are taken to the Constitution and not the president for a very specific reason.
Right there on its website, the FBI says the bureau and its officials must only swear an oath to the Constitution — not even a president. The reason? Because the latter “too easily leads to tyranny”:
It is significant that we take an oath to support and defend the Constitution and not an individual leader, ruler, office, or entity. This is true for the simple reason that the Constitution is based on lasting principles of sound government that provide balance, stability, and consistency through time. A government based on individuals — who are inconsistent, fallible, and often prone to error — too easily leads to tyranny on the one extreme or anarchy on the other. The founding fathers sought to avoid these extremes and create a balanced government based on constitutional principles.The American colonists were all too familiar with the harmful effects of unbalanced government and oaths to individual rulers. For example, the English were required to swear loyalty to the crown, and many of the early colonial documents commanded oaths of allegiance to the king.
And here's the Marines:
Officers, especially at higher ranks, have a unique position of authority and influence within the organization that could be taken advantage of for political gain. Swearing loyalty to the Constitution instead of the president or any other person means that officials cannot manipulate officers in order to gain control over the military and become dictators.
Note those words: “tyranny” and “dictators.” These are the reasons Trump's reported request of Comey was so out-of-bounds and why it was probably a pretty easy question for Comey to answer.
And for a president who has often expressed admiration for authoritarian leaders and little patience or regard for the rules and norms that constrain his presidency — whether the filibuster, on executive actions or with the judiciary — it seems pretty par-for-course.