Television was banned as un-Islamic by the Taleban
A new law guaranteeing freedom of the press in Afghanistan has been formally inaugurated.
The new law gives written guarantees for a free press, and Mr Karzai said it left Afghan journalists free to criticise the government.
"People can have their newspapers, people can have their radios and they can write things, they can criticise us as much as they want," he said.
Censorship
The new law ends years of censorship and a total ban on free speech under the former Taleban regime.
Television was banned while radio and print offered little more than propaganda for the former regime.
Any form of criticism was ruthlessly suppressed.
BBC Kabul correspondent Kate Clark was thrown out of the country a year ago as the Taleban prepared to destroy the famous statues of Buddha in Bamiyan province.
"I used to wake up in the middle of the night agonising over reports that I had made because I didn't want anyone to get into serious trouble," she says.
"It did feel that dangerous. People risked their lives to tell me information."
The fall of the Taleban has seen one of the freest periods of publishing since the communist coup 20 years ago.
Independent
Broadcasting and most papers remain state-controlled, but a number of independent magazines are now available on the streets of Kabul.
Among them is a weekly magazine called 'Women's Mirror', the first publication in Afghanistan written exclusively by women for a female readership.
Some writers here have already started to ask questions about corruption and accountability.
But ensuring such freedom of expression in a country where local warlords control many of the provinces could prove a major test of Hamid Karzai's administration.