Three words for Shinzo Abeand for history. Three words: including Senkaku islands (was Obamas omission of the definite article the, one wonders, part of a subconscious hesitation?). Thus a US president for the first time explicitly committed his country to defend Japan if it should come to blows with China in their territorial dispute.

Barack Obama affirmed that the islands were covered by Article V of the Japan-US Security Treaty which states: Each Party recognizes that an armed attack against either Party in the territories under the administration of Japan would be dangerous to its own peace and safety and declares that it would act to meet the common danger in accordance with its constitutional provisions and processes.

While no different from the position enunciated previously by other members of his administration, in its language and settinga joint news conference with Abe standing alongside him during a state visit to JapanObamas endorsement of the status quo in the East China Sea was significant. It is exactly what Abe wanted to hear, after months of anguished commentary in the Japanese media suggesting the US might be turning into a fair weather ally. But the comparatively muted official response from China is also interesting: a sign that Beijing heard the president when he said he was not stating a new position. The words might be on the record, but was there is any greater will behind them?

A visit by a US president to Japan as a state guest (the most elaborate form of diplomatic visitation) is uncommon. The last one was 16 years ago. Reportedly the Americans took some persuading to set aside the minimum three days required. Such occasions can serve to elevate a bilateral relationship to a new level, and they can draw attention to areas of disagreement as well as agreement. On the territorial dispute, for instance, the main focus was on the US commitment to fight alongside Japan. Obama, however, also stressed the importance of dialogue to resolve the dispute, and avoiding escalation, which implicitly binds Japan to keep its power dry.

As for the other big-ticket item on the agenda, trade liberalisation, Japan had hoped the impetus of a state visit would deliver an agreement. The strategy came up well short. Instead of sweetness and light, the impression gained in Tokyo was that the Americans were intent on extracting the highest price, in economic terms, for those three choice words on security. (Having said that, insiders already knew that Obama lacked the clearance from Congress to strike a deal with Japan, and nothing less than a trade coup would allow him to presume on Congresss approval.)

Abe took a gamble early in his second administration when he went against the protectionists in his governing Liberal Democratic Party and led Japan into the Trans-Pacific Partnership. While trade liberalisation is necessary for his program of economic revitalisation, the disruptive risks of increased import competition, particularly in the agricultural sector, are not inconsiderable. Japans farming communities are the most exposed to the effects of an aging society, and there are far fewer employment alternatives in regional and rural areas than in the big cities. Farmers are a well-organised lobby group in a country where all politics is local.

In the TPP negotiations, the Americans are seeking a better deal on beef than was recently obtained by Australia, and they want a broader agreement to include various other farm goods, automobiles and intellectual property.

Japans TPP Minister, Akira Amari, is showing signs of wear and tear, admitting publically that if he were ever asked to do the job again, he would refuse. Amari and his US counterpart Michael Froman have held 25 hours of face-to-face negotiations, continuing even as Abe and Obama were tucking into their Ginza sushibut without result. At one point it seemed Obamas visit would end with no joint communiqu, which certainly would have left a bad taste. Officials eventually managed to cobble together a communiqu that reiterated the presidents statement on the Senkaku dispute and supported Abes drive to reinterpret the Japanese constitution to embrace the right of collective self-defence (hardly surprising, since this is already assumed in the bilateral security treaty quoted above). But when it came to the TPP talks, the document turned to fairy floss: Today we have identified a path forward on important bilateral TPP issues. This marks a key milestone in the TPP negotiations and will inject fresh momentum into the broader talks. It takes some cheek just to write that down. Japanese sources claim the Americans held the communiqu hostage, delaying its release in an effort to wring extra trade concessions from Japanif so, all that resulted was sweet talk.

Without a substantial trade deal soon the Obama administration risks a loss of domestic support for his much touted rebalance to Asia. Likewise some of the gloss will come off Abes can-do image, particularly the credibility of his claim to want to break down structural rigidities in the Japanese economy. For all the pomp and ceremony, and three-star sushi, the two nations only managed to reaffirm the oldmilitarybasis for their relationship rather than define the new.

For the Japanese, an unwanted byproduct of the state visit has been to draw attention in the US and elsewhere, through media commentaries and analysis, to Abes pivot to the right since he returned to office in 2012. Some observers are discovering this issue for the first time, while others have looked for fresh evidence from Obamas visit with which to refine their sense of where events might be headed.

For the first group, it is always possible to overstate the situationit is worth reiterating that Japan is not rearming, muzzling its news media or abandoning its democratic institutions. Nevertheless there are signs of a nationalistic revival, amid a period of heightened regional tensions. Against this background, the take out from Obamas visit, I think, is disappointing. Having gone to Tokyo, he could not have said less than he did on the territorial issuethough he might have said more, for instance, on the mechanism by which the disputing parties might enter a dialogue. He came across more like a tourist than a statesman willing and able to engage Abe on fundamentals. If President Obama once seemed to represent a fresh, inclusive and future-oriented style of leader, he brought little or nothing of that to Tokyo. Which is more the pity, since he came at a time, without doubt, when Japanese are questioning whether what has served them well for almost 70 years can see them safe and strong into the future.

Walter Hamilton reported from Japan for the ABC for 11 years.