“He has four eyes and four ears,” Koichi Fujishiro, a former chairman of the Yokohama City Council, said in a telephone interview. “He worked from morning to late at night.”
In 1996, Mr. Suga leapt to national politics, winning a seat in the lower house of Parliament. During Mr. Abe’s first, fumbling stint as prime minister, from 2006 to 2007, Mr. Suga served as minister of internal affairs and telecommunications. Even after Mr. Abe left office following a series of scandals, Mr. Suga remained loyal.
Mr. Abe rewarded that loyalty when he came back as prime minister in 2012 and chose Mr. Suga as his chief cabinet secretary. According to Kenya Matsuda, author of “Shadow Power: Chief Cabinet Secretary Yoshihide Suga,” Mr. Suga urged Mr. Abe to focus on the economy rather than the nationalist agenda that had consumed his first term.
Last year, Mr. Suga took some steps to come out of the shadows. When the government officially unveiled the name of the new era to mark the enthronement of Emperor Naruhito, it was Mr. Suga who dramatically revealed a calligraphic rendering of the name, Reiwa, earning him the sobriquet “Uncle Reiwa.”
Mr. Suga has also trumpeted his brainchild, a system that allows citizens to donate money to local governments in exchange for locally sourced gifts. Many small-town governments, however, have lost money by spending more on gifts like marbled Wagyu beef or shipments of fresh lobsters than they raised in donations.
On foreign policy, Mr. Suga has worked to fill holes in his portfolio. He visited Washington last year, the first chief cabinet secretary to make such a trip in three decades.
For Mr. Abe, personal diplomacy with President Trump was crucial. If Mr. Trump wins re-election, the question, said Ms. Solis of the Brookings Institution, “is whether Suga can work the magic, or whether that was a bromance between Trump and Abe not to be repeated again.”