Updated at 10:35 a.m. ET
BERLIN This city may be the only place in the world where President Obama's rhetoric is no match and can be no match for the presidents who came before him.
Mr. Obama made symbolic history of his own as the first president to speak from the eastern side of the gate, looking it what once was an East Germany guarded with barbed wire, dogs and sharpshooters.
The biggest news in Mr. Obama's speech focused on arms control with Russia, a topic far less volatile than it was during the Cold War arms race but one near to the president's heart. Mr. Obama called for deeper cuts in both nations' nuclear arsenals - up to a third - and do so under dismantling guidelines set forth in the New START Treaty signed with Russia in 2010.
The president also called for moving "beyond Cold War nuclear postures" and rejecting "the nuclear weaponization" pursued by countries such as North Korea and Iran.
"Peace with justice means pursuing the security of a world without nuclear weapons," Mr. Obama said.
Mr. Obama, as other presidents have, spoke German. But he cannot match the electrifying and defiant Kennedy declaration "Ich bin ein Berliner" (I am a Berliner).
Though that is the soundbite of the speech, Kennedy said so much more about the epic struggle between the free-market, democratic West and the statist, armed and communist East. Kennedy laid rhetorical foundations history, bipartisan U.S. foreign policy and future presidents built upon.
"There are many people in the world who don't understand, or say they don't, what is the great issue between the free world and the Communist world," Kennedy said.
"Let them come to Berlin. There are some who say that communism is the wave of the future. Let them come to Berlin. And there are some who say in Europe and elsewhere we can work with Communists. Let them come to Berlin. And there are even a few who say that it is true that communism is an even system, but it permits us to make economic progress. Lass' sic nach Berlin kommen. Let them come to Berlin."
Berlin stood then and still does as the resilient and unbeatable answer to a long-forgotten Soviet desire to dominate the economic, political and cultural destiny of Europe. Berlin and the west said no. A line was drawn with more permanence and strength than the Berlin Wall, an edifice to unrealized Soviet ambitions President Reagan mocked at the Brandenburg Gate in 1987.
"Standing before the Brandenburg Gate, every man is a German, separated from his fellow man. Every man is a Berliner, forced to look upon a scar."
Adding to Kennedy's "come to Berlin" comparisons of East and West, Reagan taunted the Soviet leadership.
"In the West, we see a free world that has achieved a level of prosperity and well-being unprecedented in all human history. In the Communist world, we see failure, technological backwardness, declining standards of health, even want of the most kind -- too little food."
Though at the time, Reagan's later injunction for Soviet Leader Mikhail Gorbachev to "open this gate" and "tear down this wall" seemed fanciful and diplomatically hazardous, it now looks and sounds prophetic. And utterly in step with Kennedy's rejection of Soviet supremacy.
When Bill Clinton came to the Brandenburg Gate in 1994, the wall had fallen, Germany was reunified and and Berlin was whole. Clinton touchingly hailed Germans who knocked down the wall one hammer blow at a time, saying they had, for all the world to behold, "turned your dreams of a better life into the chisels of liberty." Clinton concluded by saying "Nothing will stop us. All things are possible. Berlin is free."
Especially when you consider Mr. Obama already tried to give a speech at the Brandenburg Gate in 2008 but had to settle for the Tiergarten nearby. German Chancellor Angela Merkel, who is treating to state dinner honors now, nixed the Gate backdrop as reserved for actual U.S. presidents and found candidate Obama's presumptuousness "odd."
Some 200,000 gathered for Mr. Obama nonetheless and as a witness to that fevered reaction I can say it had little or no precedent on the continent or American political history. Mr. Obama was more than a candidate or office-seeker.
In the eyes of Germans and europeans who trained and bused in for the event, Mr. Obama was something intangibly larger with humanist aspirations and an ethic that seemed dizzingly above politics. Mr. Obama understandably basked in the glow, declaring himself not only a proud American, but "a fellow citizen of the world." The German press tried to comprehend the adoration and absorption of the moment.
Now Mr. Obama is in his second term and Germans are ticked about U.S. counter-terrorism surveillance. Some have unfavorably compared it to the bad old days Kennedy and Reagan railed against.
Merkel will try to pry some answers loose from Mr. Obama as she eyes her own re-eletion bid in September.
And Mr. Obama is hemmed in by his own 2008 rhetoric on climate change. The just-completed G-8 summit said almost nothing on the subject and long-pending regulations from Mr. Obama on limiting emissions from coal-fired plants in the U.S. still await action even as Obama privately dismisses routine environmentalist protests over the also-pending State Department decision whether to approve the Keystone XL pipeline.
Mr. Obama warned in his second inaugural address about climate change and routinely points to intensified weather patterns as a sign change must come in terms of carbon dioxide emissions. But that rhetoric sounds a lot like 2008.
"This is the moment when we must come together to save the planet," Mr. Obama said then. "Let us resolve that we will not leave our children a world where oceans rise and famine spreads and terrible storms devastate our lands. Let us resolve that all nations - including my own - will act with the same seriousness of purpose as your nation and reduce the carbon we send into our atmosphere."
On climate change and surveillance, to name just two issues, Mr. Obama looks much different here than he did five years ago.
He set a standard as a candidate he might not be able to match Wednesday in terms of crowd size, excitement or sense of possibility. And he already has a tough rhetorical bar to cross. Not his, but his predecessors'.