Jon schreef:
http://en.wikipedia.org/wiki/Socialism
Here is my question... the info box it red.
That is not an infobox; it's an article series box. A small difference, but (in my opinion) it does make a difference. Box templates are designed to give a number of articles an uniform look, and the type of box determines its scope, and how it should look.
The Socialism series box is placed on many articles about various aspects of socialism; since socialism is the subject of the entire series, it is not that strange to make the series box a socialist red colour.
If [[Socialism]] had an infobox, that box would likely be used on a number of political ideologies, and it should look the same on all of those articles. Infoboxes should rarely (never?) be styled to suit the individual articles. (See for example the discussion at [[Talk:Wales]] about the infobox on http://en.wikipedia.org/w/index.php?title=Wales&oldid=203877423.
Eugene