Because Mudcat allows more debate on certain topics than 'most' forums, it is easy for people with uncompromising views & attitudes to get carried away in expressing themselves.... and that brings out those who have disagreements with both facts & mode of expression.... which means that "mode of expression" often turns to insult, invective and characterizations of personality.
   The idea of debating only the position instead of labeling the person seems to be lost on many.
It is also the case... (and I have seen it admitted several times).. that some just simply relish the process of contentious argument and seem to consider it wimpy to back off & defuse things when the temperature gets too hot.

There are several mindsets that are displayed in these situations... one is the "my mind is made up... don't confuse me with facts" type. Another is the use of "righteous indignation" to justify almost any invective in one's defense.. or attack... of some particular cause or idea. Then we see added in cultural/religious/political "hot buttons" which can bring out immediate, knee-jerk responses for some. When these are combined, threads are closed & posts deleted.

Now... read again what I just said, and note that I made no reference to ANY specific issues.... yet I would not be surprised to see reactions such as: "I suppose you meant ME in point 3a!" or "You know that point 5 is exactly how whatisname acts when anyone mentions XYZ!" This has already happened above as various well meaning folk automatically switch into defending or attacking their favorite specific issue.

There is also the misconception that 'liberal' and 'conservative' are just 2 sides of the same coin. In reality, there are two very different thought processes involved in a lot of the issues in the two basic attitudes. It is not always immediately apparent, but can be seen by exploring the implicit premises involved... if you can get anyone to even discuss the actual basis and reasoning by which they arrived at their positions.
It is not always even a matter of 'right or wrong', because it is possible to be 'right' about some things, while using atrocious logic & explanations... and possible to have an air-tight reasoning process and be 'wrong' due to just simply beginning with faulty premises.

(I'm still not pointing a finger directly at anyone... but as Pete Seeger said about his song "Waist Deep in the Big Muddy".... "I didn't name anyone... I'm just a shoemaker, going around making shoes- but if the shoe fits...")