Sarkozy, after all, campaigned against the excesses of 1960s leftism.
The trouble is this: when “leftism” becomes an identity element, it makes leftist politics involuntary.
1917, from left in the political sense + -ism.
1897, from left (adj.) in the political sense + -ist.
One who holds a left-wing viewpoint; someone who seeks radical social and economic change in the direction of greater equality.