Tenet being the wotd, it raised my interest in the comparison between doctrine and dogma, like I needed an excuse to discuss a word...
Doctrine comes from the Latin "doctrina" for "teaching", and still retains that meaning of a principle, position or policy that is taught (see indoctrinate). Dogma comes from Greek "dokein" for "to seem good, think" through Latin "dogmatos" for "that which one thinks is true". And tenet simply comes from the Latin "tenere" for "to hold", as in something (an idea or belief) which is held. Contextually, doctrine and dogma are used interchangeably, and all are listed as synonyms for each other, but, if we haven't already learned that by now, it bears repeating that there are no true synonyms.
So, I'll start with tenet which is a belief that one holds, and bears no relation to the truth of the belief or where one got the belief or what one does with the belief. Theoretically, you could hold a false tenet (a belief that has been disproved, but while one still clings too), since it is just a belief, and there is no implied requirement to impose a tenet on anyone else in any way. Dogma is a belief that may or may not be true, but one thinks it is true, still having no relation to how one got the belief or what one does with it. Perhaps this word has the greatest relation to faith, believing in an idea which cannot be demonstrably proven or disproven, but which is embraced as true, regardless, and therefore, dogmas are more abstract. This may also explain why dogma is most frequently associated with the church, and particularly, the Catholic church. Doctrine, then, is a belief that is taught, again, with no relation to the truth of the belief. We hope it is true, and perhaps by teaching it, we make it true because we have spread the knowledge far and wide, but the real distinction of this word is that it is something that is intended to be communicated to another for them to accept. Yes, conversion is an issue in religion, but not through dogma. It would be church doctrine to baptise all heathens, but the dogma would be to accept God. The heathen, so converted, may then choose to accept the dogma as a personal tenet in their daily life. Now, take this out of the religious context, and we have, it is the corporate doctrine to recruit the best and the brightest to solve the problems of the humanity, but the dogma would be to accept the capitalism, and Human Resources hopes that each employee embraces the tenet of "the good of the company" over "the good of the individual". Or, politicians push new doctrines in the form of proposed legislation, but the dogma of the country is democracy for all, while some taxpayers and constituents hold contrary tenets of the benefits of small versus large government. Ok, well, I think you get the point.
Now, do these words get misused? You bet! Dogma, still carrying that religious overtone, gets associated almost entirely with the religious sphere of influence, as does tenet, without distinction, while doctrine gets the non-religious. Which makes using dogma in a non-religious context tending to elevate the subject to religious fanatacism (tenet not as much, but still), and using doctrine in a religious sense tending to diminish the religious importance. However, like expiate v. atone, I prefer to emphasize the religious connotation in furtherance of the sarcasm, so dogma it is for me in casual conversation, and I'll stick to the absolute distinction for my oral and written advocacy in the formal settings. And tenet is still, just tenet, but it did start this particular discussion.