I think that you have to make the distinction between tenure and tenure track faculty and teachers. There is a very distinct difference between those two things.
A teacher went to school for their bachelor's degree or teaching certificate and may well have also gotten their masters. A tenure track or tenured faculty member went beyond that, got their PhD and has had their dissertation, in most cases, published. There is a significant amount of difference between the two and I don't think you can argue both in the same arguement.
Teachers in every state are underpaid (for the most part). Sure some teachers are paid more than enough for what they do, but the reality is that teaching the youth (elementary school, grammar school, etc) is perhaps one of the most vitally important jobs in our country. If the youth are not taught then our country falls completely apart at the seems. I also come from a family of teachers and I can say this, most teachers work very hard to do what they can to meet the needs of young students, young students that are required by law to attend school. That is very important because teachers in the State of Indiana have the responsibility to make sure that every student they come into contact with is in some way educated. I have heard the arguements from the Teacher's Union in Indiana and it simply doesn't hold water. There arguements would be different if there was not a recession, but their is and everyone is suffering.
Now on to the faculty at ISU, Purdue, IU, etc. Yes most faculty work hard to "teach" their students. Most, but not all, have research requirements. Several go on sabatical for the purposes of that research. However, unlike elementary and secondary school teachers the faculty, in most cases, have some form of graduate assistant, teacher's assistant and/or research assistants (especially if they are in a research "centric" area such as the sciences.) They have a significant amount of assistance for the research they may be doing (of course some don't, but overall their is assistance available to them). I am sure most of you had a TA as your instructor in a course...not the actual faculty member themselves. Tenure Track and Tenured faculty have, from my perspective, the best of both worlds. They can research and study what they are passionate about, yet they do not have the grind of a 40 hour work week. Sure they may put in more hours than that, but it is studying a "hobby or something they are interested in" that they love or the study of their subject will eventually lead to monetary gain for them if they were to publish their findings in a textbook or book.
Most faculty at ISU work very hard, and most are not forced to teach summer courses. It is usually the case that the faculty desire to teach in the summer because they can make up to 30% of their base salary for teaching courses in the summer. So in other words is the faculty member had a base salary of $75,000 per year they could make an additional $22,500 in summer months if they teach a full load in the summer. In other words their base salary plus the summer would mean that they actually made $97,500 for the year.
IMO faculty don't realize how nice they have it. They might work outside the classroom, they might spend many "hours" working outside of "traditional" hours or work. But, unlike probably 75% of the working population that have assistance, they have support, they several breaks, etc. They have a great gig that anyone would love to have. In other words, you go tell the guy that just got laid off as the asst. plant manager somewhere that he could go back to school at ISU and start working on his PhD and could be tenure track within 2 years and be paid as well as most professors are, HE WILL JUMP AT THE CHANCE TO DO SO!!!! To go from a stress filled, high pressure, difficult, deadline centric job to a professorship....anyone would jump at that. I am not saying that faculty don't have the right to complain. But I have to agree with the letter...understand your audience and whom will hear what you are saying. There is a policital issue here and the faculty should realize that complaining publicly about doing what is perceived to be your job when well over 10% of the citizens of TH don't have a job...not a good idea at all!!!!!