Pearl Harbor and Hiroshima-Nagasaki represent book-ends enwrapping the most devastating era in Japan-U.S. relations, the Pacific War. It is fitting that in the 75th anniversary year of the Pearl Harbor attack, President Barack Obama became the first sitting president to go to Hiroshima, and on Dec. 27, Prime Minister Shinzo Abe is making the first official visit by a Japanese prime minister with an American president to Pearl Harbor. (Prime Minister Shigeru Yoshida made a short, almost-forgotten visit in 1951.)

Neither visit is about apologizing, at least not directly. Both men are paying tribute to lives cut tragically short, particularly those of the other country. These reciprocal acknowledgements of the other’s victims cannot lay to rest all the ghosts of the war, but they represent another important symbolic step forward in setting history behind and in further consolidating the present close relationship. This is of critical importance to two countries that need each other more than ever.

It is surely a tribute to the wisdom and flexibility of American postwar policies and to the vagaries in international politics that America’s foremost World War II enemies, Japan and Germany, are among its staunchest allies. Separated by geography and deep cultural differences, the reconciliation between Japan and the United States is the more remarkable story.

Beginning as an occupying force following the war, the United States soon became a critical partner in Japan’s postwar rebuilding and prosperity. The Occupation, with the help of many Hawaii nisei, went far more smoothly than expected in part because of high policies and in part because of individual acts of friendship. For example, Fujio “Wymo” Takaki of Mokuleia found cherry tree seedlings for the devastated city of Maizuru to encourage the people. Today the Aloha Sakura monument stands there as a testimony to Japan-U.S. friendship.

Nonetheless, controversy over security and economic issues long troubled the two countries’ relations. In 1960 massive demonstrations in Tokyo over the U.S.-Japan security treaty caused the cancellation of President Dwight Eisenhower’s trip. As late as the 1980s, it was controversial in Japan to refer to the relationship as an “alliance.” And from the late 1960s through the early 1990s, contentious trade issues dominated.

Today, according to Pew Research polling, the first item that pops into most Americans’ minds when asked about Japan is sushi, not trade. A majority of Americans see Japan as a “fair trader,” a huge shift over 20 years. The alliance is now strongly rooted in public approval. Three-fourths of Japanese have a fair amount or great deal of trust in the United States, while two-thirds of Americans feel the same way about Japan.

China has certainly been a factor in this change. The United States remains the world’s foremost power, and Japan is the richest, most technologically advanced country in Asia. But with China’s rise and global power increasingly fragmented, neither the U.S. nor Japan loom as large as they once did.

Both countries were instrumental in China’s rise — the U.S. as a market and Japan as, at one time, its largest aid donor. But both, especially Japan, are deeply concerned about China’s future direction.

Today Japan and the United States need to stand firmly together, along with other allies, in support of a rule-based order that includes China’s positive engagement. But this also represents a complicated challenge in effective, respectful Japan-U.S. consultations.

Too often over the past 70 years, usually due to domestic politics, either Japan or the U.S. has undertaken or cancelled an initiative or policy affecting the important interests of the other, often with no or only minimal notice.

A truly effective partnership, however, cannot be taken for granted and should gradually become more equal, as is slowly happening in the case of Japan and the U.S. Like Wymo Takaki’s cherry seedlings, an alliance requires careful and constant tending. With their reciprocal, well-planned visits, President Obama and Prime Minister Abe are doing just the right thing.

Dr. Charles E. Morrison will be stepping down at the end of this month after 18 years as president of the East-West Center. His successor is EWC alumnus, Dr. Richard R. Vuylsteke.