By Lucky Gold, CNN
Imagine a world where the Berlin Wall came down – and went right back up again.
On Monday, an extraordinary tweet was sent by Thomas Erdbrink, Tehran bureau chief for The New York Times.
“Is Iran's Berlin Wall of internet censorship crumbling down? I am tweeting from Tehran from my cell [phone] without restrictions.”
And he wasn't alone. Suddenly, Iranians were able to access Twitter and Facebook without side-stepping government firewalls – a freedom of expression almost unknown since the 2009 election of Mahmoud Ahmadinejad, and the crackdown against his political opponents, both inside and outside the country.
Iranian internet users were euphoric Monday, and they were quick to credit their new president, Hassan Rouhani, who has his own Twitter and Facebook pages, and has encouraged the free-flow of information amongst people.
Even Iran's new foreign minister is an avid tweeter.
Then, just as suddenly, the tweets took a different and mysterious turn. Iranians awoke to find social media blocked once again, while the government insisted that the brief internet interlude was just "a glitch."
Or was it?
Some see it as a deliberate test of boundaries in a new Iran. Others say it reflects a political struggle within the leadership.
Glitch or government policy, something has changed.
Iran's foreign ministry confirmed today that Presidents Rouhani and Obama have exchanged letters.
It is the first direct communication between leaders of the two countries since diplomatic relations were severed in 1980.