By Sam Wilson
BBC News, Berlin
"It feels better than ever before in Germany now," says Harry Kaesmacher.
It is only half an hour since Germany knocked Argentina out of the World Cup on penalties, so he may be heady with victory, but he sounds convinced.
Since the reunification of Germany in 1990, he says, "we have been a little bit not sure, divided - but now we all take this feeling together and make a better Germany. I feel it all over the country."
Many Germans feel football success would make them feel less divided
Harry and his friend Karsten Wilke are among the tens - probably hundreds - of thousands of people who watched Germany's quarter final in the "Fan Mile" that stretches between two of Berlin's most famous monuments, the Brandenburg Gate and the Siegessaule triumphal column.
"It was an amazing game," says Karsten, "but I always knew we'd win, and become champions".
For a while, his compatriots were not so sure. After a goalless first half described as "boring" by several fans, Argentina took the lead.
The atmosphere on the Fan Mile grew steadily more tense, with Germans urging their team onto the attack, and nervous whenever Argentina advanced.
It was only late in the game that Germany equalised, but the roar and celebrations were more than relief - people now were sure Germany would go on to win.
It appears most football fans here are certain that, having disposed of Argentina, one of the favourites, their team can now lift the cup.
Destiny seems to be pointing to a German victory
There is a billboard in the Potsdamer Platz that harks back to Germany's previous World Cup triumphs.
It says: "1954 Bern; 1974 Munich; 1990 Rome; 2006 Here!"
Another says: "Statistically, Germany are always World Champions in Germany."
There is a growing feeling almost of destiny - that Germany's biggest triumph yet will come in its most important and historic city.
Harry Kaesmacher believes it will be a "key moment" in post-reunification Germany, that will bring this still-divided country together.
The German team, he says, will be a symbol.
"We have not the best players, but we have the best team - coach, players and fans, everything together, the best spirit."
Some areas of the former East Berlin have done very well since reunification. In Georgenstrasse, half a mile north-east of the Brandenburg Gate, a string of antiques and crafts shops occupy a cloistered strip.
Priti Shambu, proprietor of a leather goods shop, says it is not the same throughout old East Berlin.
"Because of the bad economic situation some [in the east] are too jealous to take part in the uniting," she says.
"And I know some people [in the west] who still don't come to the eastern part."
But things are changing slowly, she says.
"Young people now they go everywhere they want, to the eastern part, to the bars, the restaurants and it is no problem."
She believes the World Cup can play a role.
"It may be a final point. We have been united for 16 or 17 years, it is a slow process, but maybe this is the high point of the uniting.
"The mood till today has been so good," she said, speaking before the match took place. "I hope if they lose today they will not be angry, and the mood will stay good."
At Humboldt University in the former east of the capital, Hartmut Haussermann, professor of urban sociology, is sceptical.
"It is too early to say," he says. "There is definitely something, but at the same time we should not overestimate it.
"We have to see if there is any long-term effect."
Value of victory
Mr Haussermann points out that parts of East Berlin are still very deprived compared with the west. Some 80% of industrial jobs in the east disappeared within a few years of reunification, and this has still not been corrected.
And there is still "political and cultural cleavage", whereby the East votes for the post-communist party and the two parts of the city read different newspapers.
He recognises the value of victory at the World Cup.
"All 'German' successes were West German successes. Now the East can participate if the German team is successful. So it's important that we are united in this field," he says.
"What it already does is bring some feelgood factor. This is good for Berlin. The feeling of being disadvantaged and depressed is the normal feeling for Berlin. Now some hilarity has come to the city."
The "hilarity" was certainly not lost on Harry and Karsten.
"This is a great atmosphere," said Karsten. "We are staying here and will party until we have to get the train back to Cologne at 4.30am."