The 2025 Elections to the Upper House of the Japanese Parliament: Lessons for the Political Mainstream

The article analyzes the results of the elections to the House of Councillors of the Japanese Parliament, held on July 20, 2025, in which the ruling coalition of the Liberal Democratic Party (LDP) and Komeito was defeated and found itself in the minority. The author examines in detail the reasons for the electoral success of the right-wing opposition parties, above all the Sanseito party, which significantly displaced the LDP in the upper house. In addition to the poor economic situation in the country, the voters’ disappointment with the LDP’s insufficient measures to eradicate political corruption, and the shrinking of Komeito’s electoral base, an important reason was the general crisis of public confidence in Japan’s traditional political establishment, as well as a sharp increase in anti-systemic sentiments in Japanese society. A significant segment of the conservative electorate swung towards the political alternative provided by the populist parties – Sanseito and the Democratic Party for the People. These parties have found a new and very effective tool for influencing the masses – social media and streaming channels, through which they have managed to mobilize the “floating votes” of the conservative electorate. Thus, the failure of the LDP and Komeito and the successes of the opposition parties were facilitated by a surge of public interest in the elections against the background of widespread public discontent with the current government.

1. Kniga Sanseito (2024). Sanseito Book. Sanseito. September, 8 pp. (in Japanese). Available at: https://sanseito.jp/pdf/sanseito_book_2409.pdf, accessed 17.08.2025.

2. Nevskaya T.A. (2018). The role of social networks in the electoral process in modern Russia. Politics and Soci‑ ety. No. 9, pp. 31–39 (in Russian). DOI: 10.7256/2454-0684.2018.9.27460.

3. Purnendra J. (2025). LDP’s historic electoral defeat upends Japan’s politics. East Asia Forum. 27 July. DOI: 10.59425/eabc.1753610400.

4. Rehm M.X. (2025). Ishiba walks a political tightrope on immigration. East Asia Forum. 19 July. DOI: 10.59425/eabc.1752930000.

5. Scartozzi Cesare M. (2017). Hereditary Politics in Japan: A Family Business. Second-generation politicians are increasingly entrenched in Japan’s Diet and government. The Diplomat. February 09. Available at: https://thediplomat.com/2017/02/hereditary-politics-in-japan-a-family-business/, accessed 17.08.2025.

6. Streltsov D.V. (2021). Hot political autumn in Japan. Far Eastern Stu‑ dies. No. 6, pp. 7–21 (in Russian). DOI: 10.31857/S013128120017350-6.

7. Streltsov D.V. (2024). The Political crisis in Japan: Has an Escape Taken Place? Asia and Africa Today. No. 12, pp. 14–23. DOI: 10.31857/S0321507524120022.

8. Taniguchi N. (2025). How Social Media Is Reshaping Politics in Japan – for Better or Worse. Nippon.com. June 4. Available at: https://www.nippon.com/en/in-depth/d01134/, accessed 17.08.2025.