BERLIN // Issuing an appeal for a new citizen activism in the free world, Barack Obama yesterday renewed his call to reduce US and Russian nuclear stockpiles and to confront climate change, a danger he called "the global threat of our time".
In a wide-ranging speech that listed the challenges facing the world, the US president said he wanted to reignite the spirit that Berlin displayed when it fought to reunite itself.
"Today's threats are not as stark as they were half a century ago, but the struggle for freedom and security and human dignity, that struggle goes on," Mr Obama said, standing at the city's historic Brandenburg Gate. "And I come here to this city of hope because the test of our time demands the same fighting spirit that defined Berlin a half-century ago."
The president called for a one-third reduction of US and Russian nuclear stockpiles, saying it was possible to ensure American security and a strong deterrent while also limiting nuclear weapons.
His address came nearly 50 years after John F Kennedy's famous Cold War speech in the once-divided city. Shedding his jacket and at times wiping away beads of sweat, the president stood behind a bulletproof shield as he addressed the crowd of about 6,000.
It was a stark contrast to the speech he delivered in the city as a presidential candidate in July 2008, when he attracted a crowd of 200,000 to embrace his vision for American leadership.
Whereas that speech soared with his ambition, this time he came to caution his audience not to fall into self-satisfaction.
"We must acknowledge that there can at times be a complacency among our western democracies," he said. "Today, people often come together in places like this to remember history, not to make it. Today we face no concrete walls or barbed wire."
The speech came just a week before the anniversary of Kennedy's speech in which he denounced communism with his declaration "Ich bin ein Berliner" (I am a Berliner). Mr Obama, clearly aware that he was in Kennedy's historic shadow, asked his audience to heed his predecessor's message.
"If we lift our eyes as president Kennedy calls us to do, then we'll recognise that our work is not yet done," he said. "So we are not only citizens of America or Germany, we are also citizens of the world."
The president has previously called for reductions to nuclear stockpiles. But by addressing the issue in a major foreign-policy speech, Mr Obama signalled a desire to rekindle an issue that was a centrepiece of his early first-term national-security agenda.
He discussed non-proliferation with Russian president Vladimir Putin when they met on Monday on the sidelines of the G8 summit. During Mr Obama's first term, the US and Russia agreed to limit their stockpiles to 1,550 as part of the New Start Treaty.
In Moscow, Yuri Ushakov, a Russian foreign-policy aide, said plans for further arms reduction would have to involve other countries.
"The situation is now far from what it was in the '60s and '70s, when only the USA and the Soviet Union discussed arms reduction," Mr Ushakov said.