| By Brian Wheeler
Political reporter, BBC News
Matthew Taylor - who stressed he was speaking as a "citizen" not a government spokesman - said the web could be "fantastic" for democracy.
But it was too often used to encourage the "shrill discourse of demands" that dominated modern politics.
He was speaking on the day Mr Blair carried out an online interview.
Mr Taylor said Mr Blair's online grilling from voters - and other initiatives such as environment secretary David Miliband's blog and Downing Street's new online petition service - showed the government was making good progress in using the internet to become more open and accountable.
But he said more needed to be done by the web community in general to encourage people to use the internet to "solve problems" rather than simply abuse politicians or make "incommensurate" demands on them.
Speaking at an e-democracy conference in central London, he said modern politics was all about "quality of life" and that voters had a "very complex set of needs".
| The internet has immense
potential but we face a real problem if the
main way in which that potential expresses itself is through allowing
citizens to participate in a shrill discourse of demands
The end of deference, the rapid pace of social change and growing diversity were all good things, he argued, but they also meant governments found it increasingly difficult to govern.
"We have a citizenry which can be caricatured as being increasingly unwilling to be governed but not yet capable of self-government," Mr Taylor told the audience.
Like "teenagers", people were demanding, but "conflicted" about what they actually wanted, he argued.
They wanted "sustainability", for example, but not higher fuel prices, affordable homes for their children but not new housing developments in their town or village.
But rather than work out these dilemmas in partnership with their elected leaders, they were encouraged to regard all politicians as corrupt or "mendacious" by the media, which he described as "a conspiracy to maintain the population in a perpetual state of self-righteous rage".
Whether media was left wing or right wing, the message was always that "leaders are out there to shaft you".
He went on: "At a time at which we need a richer relationship between politicians and citizens than we have ever had, to confront the shared challenges we face, arguably we have a more impoverished relationship between politicians and citizens than we have ever had.
"It seems to me this is something which is worth calling a crisis."
The internet, he told the conference, was part of that "crisis".
"The internet has immense potential but we face a real problem if the main way in which that potential expresses itself is through allowing citizens to participate in a shrill discourse of demands.
"If you look at the way in which citizens are using technology and the way that is growing up, there are worrying signs that that is the case.
"What is the big breakthrough, in terms of politics, on the web in the last few years? It's basically blogs which are, generally speaking, hostile and, generally speaking, basically see their job as every day exposing how venal, stupid, mendacious politicians are.
"The internet is being used as a tool of mobilisation, which is fantastic, but it only adds to the growing, incommensurate nature of the demands being made on government."
He challenged the online community to provide more opportunities for "people to try to understand the real trade-offs that politicians face and the real dilemmas that citizens face".
"I want people to have more power, but I want them to have more power in the context of a more mature discourse about the responsibilities of government and the responsibilities of citizens," Mr Taylor told delegates.
Part of the problem, he added, was the "net-head" culture itself, which was rooted in libertarianism and "anti-establishment" attitudes.
He told delegates: "You have to be part of changing that culture. It's important for people who understand technology, to move from that frame of mind, which is about attacking the establishment into one which is about problem-solving and social enterprise."
Technology should be used to encourage elected representatives to communicate better with voters, he told delegates.
Government also needed to "develop new forms of consultation and engagement that are deliberative in their form and trust citizens to get to the heart of the difficult trade-offs involved."
And there should be more effort to make communities "work together to solve problems," said Mr Taylor.
Mr Taylor is Tony Blair's chief adviser on political strategy and the former head of the centre left think tank the Institute of Public Policy Research (IPPR).
He is leaving Downing Street next week, after three years, to become the chief executive of the Royal Society for the Encouragement of Arts (RSA).