Speaking at a journalism symposium at Goldsmiths College, University of London, Dyke used the platform in part to respond to criticism of the BBC's coverage of the war in Iraq, where the corporation was accused of pro-Iraqi coverage and of failing to support British troops.
At one point, the Royal Navy axed the BBC's rolling news channel News 24 aboard the aircraft carrier HMS Ark Royal following complaints from the crew.
Sailors aboard the Navy's flagship were angered by the BBC's coverage of the war, particularly following comments made after the loss of two Sea King helicopters, which the BBC suggested was due to poor maintenance levels.
However, Dyke said today that "if Iraq proved anything, it was that the BBC can not afford to mix patriotism and journalism".
Dyke also rejected criticism from the government about keeping a BBC reporting team in Baghdad, after other news organisations pulled out: "The whole culture of BBC journalism is based on the drive for accurate and impartial reporting."
The US, he said, had already begun to mix patriotism and journalism and Dyke said that if such a trend went unchecked it would undermine the credibility of US news organisations.
"This is happening in the United States and, if it continues, will undermine the credibility of the US electronic news media," he said.
Dyke singled out Rupert Murdoch's Fox News for particular mention. The US news network has became known for its patriotic reporting and conservative views during the war. Murdoch made clear in a interview that he favoured its approach, while labelling his UK news service Sky as a "BBC light".
"Commercial pressures may tempt others to follow the Fox News formula of gung-ho patriotism but for the BBC this would be a terrible mistake. If, over time, we lost the trust of our audiences, there is no point to the BBC," Dyke said.
He defended a combative BBC interview with the American Defense Secretary Donald Rumsfeld by David Dimbleby, saying that the aim was not to trip him up, but to test his arguments and not allow him gloss over difficult issues.
"On American television today, politicians don't face that sort of interrogation. For the health of our democracy, it's vital we don't follow the path of many American networks and lose the will to do this."
He said that, in the UK, impartiality means giving a range of views, including those critical of the government.
"We [the BBC] are here for everyone in the UK, a trusted guide in a complex world. We perform this role best by exercising the freedom to air a wide range of opinion and to report the facts as best we can. In doing so, far from betraying the national interest, we're serving it."
Dyke said that the conflict in Iraq had thrown up a number of new challenges citing the rise in 24-hour news, the risks faced by embedded reporters, and unattributed and unreliable information on the internet.
"These are serious challenges for any news organisation aiming to increase the quality, as well as the quantity, of its coverage. For the BBC, as the country's most trusted source of news and current affairs, we have a particular responsibility to take account of them," he said.
He added that "while seizing every opportunity to improve the range and choice of our output, we can not afford to compromise on its honesty and integrity".
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