The risk in Asia is not of Chinese imperial plans but rather that a series of territorial disputes could spiral out of control. Most worrying is the stand-off with Japan fuelled by old enmity over the uninhabitated Senkaku Islands (known as the Diaoyu in China). Beijing declared an "Air Defence Identification Zone"  covering the airspace over the islands, primarily to test America's commitment to defend the islands and try to drive the two allies apart. This remains a source of concern.

Far from providing additional security benefits, the Pivot has worsened tensions and failed to reassure regional allies. The sense in Tokyo is that Washington cannot be relied upon to support Japan and events in Ukraine will have only intensified this perception. Japan is actually one of the few places which has responded to American exhortations to increase defence spending. However, this has backfired: Japanese prime minister Shinzo Abe's nationalist rhetoric has worsened relations not only with China but also South Korea, adding to the region's combustibility.

America's Pivot has reverberated elsewhere. A clear message has been sent to Russia and the Middle East that America's focus has shifted. Equally China appears to have abandoned nascent cooperation with the US at the UN Security Council, backing Moscow's involvement in Syria and reaching new agreements to purchase Iranian oil.

Obama's inability to articulate a concrete strategy partly explains the failure to prevent the crisis in Ukraine. The attempt at a Reset of the Russo-American relationship, where America and Russia could work together, has disintegrated. Obama failed to see the world from a perspective which didn't support the inevitable march of Western democracy, and so the "Reset" was based on the flawed supposition that the geopolitical rules of the game for Putin were the same as Obama's. Although acting from a position of weakness and with questionable strategic logic, Putin has got the measure of Obama and Nato and knows exactly how far he can push them in order to achieve his goals. Obama has repeated this miscalculation in less than a year. He mishandled the civil war in Syria, laying down "red lines" for intervention and then failing to act on them, ultimately ceding the shape of the settlement to Putin. The result was that not only did the bloodshed continue, but Russia's alliance with Syria and its regional ambitions were boosted.

Obama's failure is worse in that events in Ukraine were both predictable and entirely consistent with the recent pattern of Russian coercive diplomacy. He has allowed a situation to develop in which only two real options exist-acquiescence or war. Neither is palatable. Sanctions will have little effect on Putin; the most likely outcome will be the Russian annexation of Crimea and the formation of a government in Ukraine acceptable to Moscow.

Obama's lack of understanding of Russian security concerns is also evident in America's worsening relationship with Nato. His policy of "leading from behind", while criticising his European partners' commitment to Nato funding, has signalled a weakening of the transatlantic security arrangement. Nato has been allowed to weaken while the possibility of membership has been held out to Ukraine and Georgia. They were allowed to believe that membership of Nato was a necessary stepping stone to joining the EU. It has become clear during the Ukraine crisis that Nato has been demoted in favour of the EU as the diplomatic force behind European collective security. It is unclear whether this is a deliberate shift of policy or simply a de facto recognition of Nato's declining position. However, the Ukraine crisis has made equally clear that the technocratic EU is the wrong body for dealing with European security. It is unable to overcome the self-interest of member states in order to present a united front and coherent sanctions. The blame for not reversing Nato's decline or the haphazard process of enlargement lies with America as the senior partner and Obama as Commander-in-Chief. Nato's ill-thought-out enlargement, combined with the declining political will of its members, has led to an inevitable crisis with Russia, illustrated by its effective annexation of South Ossetia in 2008.