Japanese Prime Minister Shinzo Abe's trip to the United States last week was about as productive and positive as a state visit could hope to be. The trappings and status of the visit were second to none. It affirmed the importance of the US-Japan partnership. It produced critical, forward-looking documents to chart the course of the US-Japan relationship. Abe delivered remarks to enthusiastic and approving audiences. Significantly, there were no gaffes to muddy the message or the image he sought to present to the United States, Japan, and the rest of the world. Prime Minister Abe and his entourage should be delighted with the results.

The atmospherics were outstanding. The weather was good, Abe landed on the White House lawn to stand side by side with President Obama for his press conference, and most of the questions addressed relevant issues. Abe became the first Japanese prime minister to address a joint meeting of Congress and was given a state dinner with all of the associated buzz.

All statements, both scripted and informal, emphasized how the United States and Japan are in sync strategically and view the region and the world through the same lens. Both frame security challenges in the same way, are focused on the same sources of instability (without singling out any particular country), and back the same solutions to these problems. So, for example, Abe and Obama seek a strong international legal regime and protection for the international commons. They also see the Trans-Pacific Partnership (TPP) as not just a trade deal, but as a strategic tool to shape the Asia-Pacific region in both economic and security terms. 

The visit produced landmark documents for the alliance. They include a Joint Vision Statement for the two countries that explains their desire "to build a strong rules-based international order, based on a commitment to rules, norms and institutions," and that rests upon an "unshakeable Alliance that is the cornerstone of peace and security in the Asia-Pacific region and a platform for global cooperation." It lays out a global agenda whose realization will more deeply integrate the two governments and their nations.

      That same desire for deeper integration and partnership animates new US-Japan Guidelines for Defense Cooperation, the first re-articulation of those guidelines in eighteen years. The guidelines help modernize the alliance, reinforce deterrence, and better prepare the two countries for new security challenges. They also call for an integrated whole-of-government approach to alliance cooperation and reaffirm the US commitment to a long-term presence in Japan. Abe took particular pleasure when Obama repeated his statement last year that the Senkaku Islands fall under the ambit of the Mutual Security Treaty.

While alliance issues consumed much of Abe's visit (and are likely to have the most significance over time), his treatment of historical issues generated the most scrutiny. Abe is a conservative nationalist; some consider him to be historical revisionist, sympathetic to the Imperial Japanese regime. His speech in Washington, along with his address in Canberra earlier this year, is a window on his thinking about history. His remarks to commemorate the 70th anniversary of the end of World War II may well define his administration and the way that history assesses him.

His speech to Congress was personal and sympathetic. Abe spoke "with deep repentance in my heart," to "offer with profound respect my eternal condolences to the souls of all American people that were lost during World War II." He didn't say he was sorry but he noted that Japan's "actions brought suffering to the peoples in Asian countries. We must not avert our eyes from that." That formulation suggests that he understands a connection between Japan's actions and the suffering that resulted; it implies responsibility. In addition, he explicitly said that he "will uphold the views expressed by the previous prime ministers in this regard," a vow to honor the Murayama Statement and the Kono Statement that cannot be fudged. The speech was frequently interrupted by applause and Abe received a standing ovation more than ten times.

Some were not happy with the remarks; worryingly they spoke for groups that had the most at stake. Lester Tenney, a 94-year-old survivor of the Bataan Death March, acknowledged Abe's comments about the deceased but dismissed as "disgraceful" the failure to address the feelings of those still alive. Jan Thompson, president of American Defenders of Bataan and Corregidor Memorial Society, decried the speech as "so vague. He didn't give us one definitive sentence to send that message to us that he does know the true history."

Those who had hoped that he would address the comfort women issue were also angered. Abe noted that, "Armed conflicts have always made women suffer the most. In our age, we must realize the kind of world where finally women are free from human rights abuses," a statement that is both correct and anodyne. Reaction in South Korea in particular was bitter as he made no reference at any point - and he was asked directly about this in an appearance in Boston - to Japanese state responsibility for the comfort women.

That silence reflects a larger failure by Abe, one of three clouds on an otherwise spotless horizon. Abe didn't take up Japan's relations with South Korea in any substantive way during his visit. Of course, this visit was supposed to focus on the US-Japan relationship, but this partnership is increasingly the cornerstone of a larger network of US relations with the region. In the new US-Japan Defense Guidelines, the two countries promise to "promote and improve trilateral and multilateral security and defense cooperation." Japan's first National Security Strategy [pdf], published in December 2013, acknowledged Seoul as a potential strategic partner to Tokyo.

Abe shouldn't have devoted his speech to US-Japan-ROK relations, but he missed an opportunity to transform this vital framework and lay the groundwork for a more substantial address later this summer. In advance of Abe's arrival in the United States, National Security Council Senior Director for Asian Affairs Evan Medeiros said to reporters that "we always stress that it's important to address history questions in an honest, constructive and forthright manner that promotes healing but also in a way that reaches a final resolution," an unmistakable signal that the United States places importance not only on Japan's steadfastness as an alliance partner, but also on Japan's ability to work effectively with other allies including South Korea. A more forward-leaning approach by Abe would have given momentum to efforts underway to strengthen Japan-South Korea cooperation during this sensitive anniversary year, since a strong relationship between Japan and South Korea will strengthen Japan's strategic position in Asia while bolstering the effectiveness of the US rebalance to Asia.

The second potential cloud is the reaction Abe's words generate in Japan. Will there be explanations, qualifications, and clarifications by Abe or his entourage that undercut his message? This should not happen given the significance of his remarks - and the fact that all involved know that every word will be closely scrutinized - but even before Abe had returned home, the Asahi Shimbun reported that the statement to Congress, "I will uphold the views expressed by the previous prime ministers" - a key phrase - was rendered in Japanese as "I feel exactly the same way as the previous prime ministers." The difference is striking. 

Finally, there is the largest problem of all: Will there be continued attention to the alliance from now on or will last week prove to be nothing more than a blip on Washington schedules and a high-water mark on Abe's travel schedule? The biggest issue for Abe, one that he acknowledged during his trip to Washington two years ago, is whether Japan will be a "first-tier country." If he and his government make the joint vision statement real, the answer will be yes. The trick is turning the fine words and photo ops in to something more concrete. And that demands effort from both leaders, both governments, and both publics.

Brad Glosserman is executive director of Pacific Forum CSIS. Scott Snyder is senior fellow for Korea studies at the Council on Foreign Relations. Their book, The Japan-Korea Identity Clash, will be released on May 26. This piece first appeared in the CSISI PACNET Newsletter here.