As it marks its 66th anniversary, the fate of Japan's Constitution is set to become the focus of a political battle both in and beyond July's Upper House election.

For the first time since its enforcement on May 3, 1947, politicians have realistically started talking about revising some articles of the Constitution, breaking a long-held political taboo of the postwar decades.

The Liberal Democratic Party, led by hawkish Prime Minister Shinzo Abe, and Nippon Ishin no Kai (Japan Restoration Party), headed by the even more rightwing Shintaro Ishihara, have vowed to make constitutional revision one of their pledges for July's House of Councilors election, a move likely to stir public debate and political chaos across the nation.