Illustration: Peter C. Espina/GT

Almost 71 years after a US bomber dropped the world's first atomic bomb over Hiroshima, Obama paid a visit there while in Japan attending the G7 Summit in Ise-Shima, becoming the first sitting US president to visit the city. It is widely acknowledged that visiting Hiroshima is extremely politically sensitive for the US president, but it seems that Obama has many reasons to break the historic taboo.

The first one is to push forward his idea of nuclear disarmament and consolidate his diplomatic legacy. In 2009, Obama delivered a speech in Prague and launched his doctrine for a nuclear-free world by declaring the US' commitment to "seek the peace and security of a world without nuclear weapons." Since then, Obama has treated any achievements in this sphere, including the Nuclear Security Summits, as a significant part of his legacy. Visiting Hiroshima will again help him attract global attention and add symbolic value to his nuclear legacy.

Strengthening the US-Japan alliance to support the rebalancing strategy is another important consideration. Since the end of the Cold War, the US has increasingly relied on its relations with Japan to balance China's influence in Asia and encouraged Japan to play a bigger strategic role in its rebalancing strategy. The bombing of Hiroshima has been an issue of great historic sensitivity between the two countries, with each holding different views and arguments. Though the US didn't issue any apology, Obama's visit is viewed by some Japanese as a sort of reconciliation that will strengthen US-Japan ties.

The visit again demonstrates Obama's distinct style and doctrine in foreign affairs. Ever since he took office in 2009, Obama began reconciling relations with once-hostile countries and resolving disputes with allies and friends. His speech at Cairo University saw him extend goodwill to the Muslim world, and his decision to normalize relations with Cuba broke from long-established US foreign policy. Now in his final year in office, Obama's visit to Hiroshima is not a big deal.

Growing disapproval of the use of atomic weapons may enable Obama to take bold measures. In 1945, according to a Gallup poll immediately taken after the bombing, 85 percent of Americans approved of using the new atomic weapon on Japanese cities. But a 2015 Pew Research Center survey shows that the approval rate has dropped to 56 percent.

However, Obama has failed to distinguish which is of more importance, historic justice or personal ambition. The visit has reignited a fierce debate about the Truman administration's use of the atom bomb, one that does not help Japan reflect on its history.

Another danger is that Obama has put the US in the middle of Asia's complex historical disputes. In recent years, Japan's neighboring countries have not been satisfied with the country's stance on its war crimes during WWII. Without reflection and no sincere apology, Japan has reinterpreted its constitution and loosened post-war military restrictions. Under these circumstances, a Hiroshima visit by a sitting US president strengthens Japan's victimhood narrative instead of curbing its military ambitions, while casting doubt upon the US' position on historical issues.

The most hypocritical of Obama's visit is his lip service on disarmament. It's true that the Iran deal might prevent a possible nuclear arms race in the Middle East. But it's also true that there is obvious contrast between Obama's words and actions. The US is planning to build a new generation of nuclear weapons and nuclear production facilities, including redesigned nuclear warheads, new nuclear bombers, submarines, land-based missiles, weapons labs and production plants in the next 30 years with a projected cost of up to $1 trillion.

Hiroshima, a city that witnessed the most tragic event of WWII, should stand as a reminder as to how brutal war can be and remind Japan that it should never return to its past militarism. Regretfully, President Obama put his political ambitions first and missed the opportunity.

The author is an assistant research fellow with Institute of American Studies at China Institutes of Contemporary International Relations. opinion@globaltimes.com.cn Follow us on Twitter @GTopinion