US President Barack Obama came ready for a fighting finish, deriding Republican rival Mitt Romney as reckless and overmatched in world affairs. Instead, he found a subdued challenger who was eager to agree and determined to show he was not a warmonger. Romney starkly moderated his tone and his approach in the closing debate. Playing it safe, he tried not to unnerve undecided voters who are wary of another US-led war, or to upend a race that remains remarkably tight with two weeks to go. No moment was more telling than when Romney had a clear opening to respond to Obama's lecture that he was wrong on foreign affairs. He responded by giving his five-point plan for fixing the economy, leading to a bizarre exchange that took the debate wildly off topic. It showed how much the commander in chief was in his comfort zone, while the challenger regretted that he was not in his. The last debate turned into a mirror of the first one on October 3, when Romney had been the aggressor and Obama was intent not to challenge him fiercely. Even in trying to outline differences with Obama, Romney often started by agreeing with him. Suddenly, it was Romney the Republican who was talking about supporting economies abroad, while Obama the Democrat warned against nation-building. From drones to Afghanistan to Syria, Romney and Obama spoke in agreement on goals, if not strategy. The president's biggest vulnerability - last month's deadly assault on the US consulate in Benghazi, Libya, and all the unanswered questions that surround it - barely surfaced. Romney seemed to pass on the opportunity to assail Obama's leadership and shifting messages on the attack. Obama portrayed himself as a world leader, facing a former governor whom he said had offered positions that sent a mixed, and unsettling, message to allies and the American people. He did so at times mockingly, but faced little fire in return. "I know you haven't been in a position to actually execute foreign policy, but every time you've offered an opinion, you've been wrong," Obama told Romney. He needled Romney the businessman for complaining that today's US Navy is smaller now than at any time since 1917, trying to hold Romney up as ignorant and unfit for the job. "Well, governor, we also have fewer horses and bayonets because the nature of our military's changed. We have these things called aircraft carriers, where planes land on them." Romney's clearest points were to try to turn Obama's most aggressive moments against him, and to outline a more comprehensive strategy for combatting extremism in the Middle East and North Africa. Even then, his tone stood out. Politely. "Well, of course I don't concur with what the president said about my own record and the things that I've said," he said. "They don't happen to be accurate ... Attacking me is not an agenda." With the race extremely tight and several states hanging in the balance, Romney sought to show he was reassuring, poised and in essence, presidential. Yet he seemed to lose some of the edge that gave his campaign a bump in the first debate. Trying to capitalise on the mood of voters, Obama has campaigned as the leader who ends the wars, not the guy who begins new ones. Romney tried to combat that by saying, for example, that he would not get the United States involved militarily in Syria even though he wants to find a way to arm the opposition. Yet millions of viewers at home were often left to discern exactly how much Romney and Obama differ in a world of diplomacy that is enormously difficult and nuanced. Romney's answers often appeared driven to show he understood the regions, players and challenges instead of undermining the president's positions on them. The debate season ended with Romney looking like he wanted to get off the stage and back on the economy. That, ultimately, is where this election will be settled.