<h1>Governing party selects likely first female prime minister; must win parliamentary confirmation, rebuild trust, form coalitions</h1> Japan's governing party elected a new leader who is likely to become the country's first female prime minister; the party's internal vote was limited to its parliamentarians and dues-paying members and does not directly represent the broader electorate. The new leader will face a mid-October parliamentary confirmation, immediate policy and diplomatic tests including a potential summit with the US and obligations under existing tariff and investment agreements, and the need to rebuild public trust after recent electoral losses and funding scandals. Forming or expanding coalitions with centrist partners and negotiating cooperation with fragmented opposition groups will be legally and politically necessary to secure legislative majorities for policy and budget measures.