Responding to the tide of commentary after Newtown, Ben Alpers traces the history of the term "politicize," showing that the "verb rarely appeared at all in print until the 1960s, when its usage took off, especially in that decade's second half," when President Richard Nixon deployed the word when discussing the unrest on college campuses – thus fixing its place in the culture war canon:

Starting in 1971, the term's appearance in the Times seems to move beyond the walls of academe, to cover other areas of concern.  The AFL-CIO, for example, worried in the fall of 1971, about attempts by the Nixon administration to "politicize" the Bureau of Labor Statistics.  And positive uses of the term even show up occasionally (in January 1972, the Rev. William Jones, at an event honoring Martin Luther King, Jr., is quoted as saying "Blacks and other minorities must politicize their numerical strength and collectiveize [sic] their economic power.").  

But the conservative, culture-war quality of those 1969 and 1970 appearance of the term set the tone for the most common political uses of "politicize" in ensuing decades.