What is Zionism? The ideological question, rooted in the 19th century, has gained surprising urgency in an Israeli election campaign that seems more open than had been expected. Seeking to take votes from the nationalistic right of Prime Minister Benjamin Netanyahu, the relatively liberal opposition has rebranded itself as the Zionist Union—sparking a debate about a concept that some considered resolved when the Jewish state was declared and widely recognized in 1948. […] On the left, politicians speak of true Zionism as requiring the establishment of peace and equality in the land, including by making peace with the Palestinians and...