In a move that could significantly reshape the region’s geopolitics, Turkey has signaled that it will embark on a renewed peace process with the outlawed Kurdistan Workers’ Party (PKK). The initiative comes amid concerns that a widening of the conflict between Israel and Iran could have negative impacts for Turkey. A diminished Tehran on the regional stage is worrying to Ankara because Israel could then fill the diplomatic breach, uniting with Kurdish groups against Turkish interests.

The peace plan, spearheaded by Devlet Bahceli of the Nationalist Movement Party (MHP)—with the support of President Recep Tayyip Erdogan...