The scenes from Glenn Beck's "Restoring Honour" rally at the Lincoln Memorial in Washington, DC were astonishing. An estimated 87,500 conservative activists gathered in the US capital for a "non-partisan" rally that Beck said was intended to "reclaim the civil rights movement", falling on the 47th anniversary of Martin Luther King's "I have a dream" speech", made from the same spot.
The Tea Party movement is a phenomenal example of grass-roots activism of a kind that just doesn't exist in the UK. But this could be about to change, as it is revealed that the UK low-tax pressure group the Taxpayers' Alliance  (TPA) has been taking advice from FreedomWorks , a Washington-based organisation which says it "recruits, educates, trains and mobilises millions of volunteer activists to fight for less government, lower taxes, and more freedom".
Members of both groups attended a conference in London yesterday to transmit the strategy required to build an "insurgent campaign" of UK low-tax lobbyists. Precisely how the Tea Party model might translate to the British political system has not been made clear, but the link forged between the two organisations has received some limited coverage in the national papers.
According to the Telegraph , the TPA has experienced a near-70 per cent rise in its membership over the past year. Matthew Elliott, chief executive of the TPA, told the Guardian  that the anger at the recent HMRC errors  that led to more than a million UK taxpayers being sent demands for backdated tax payments presents a unique opportunity for his organisation. He declared:
You could say our time has come. Take the strikes on the London Underground this week and how much they annoyed and inconvenienced people. Couldn't we get 1,000 people to protest [against] that?
A protest by 1,000 does not make a movement. But the Tea Party has grown from such demonstrations to fielding its own anti-incumbent candidates in the US midterm primaries, at least proving that such a rapid rise is possible, even if the environment in which it happened bears little similarity to that of the UK.
The TPA, however, is not a comparable organisation. In existence since 2004, it lacks the novelty and sheer momentum that have characterised the rise of the Tea Party in the US. A "British Tea Party" was launched  by the Tory MEP Daniel Hannan in February, but little seems to have come of it.
For the TPA, being seen to be seeking advice from the media phenomenon that is the Tea Party is very possibly more valuable than the advice itself. However, a significant increase in grass-roots activism in the UK over the coming months is not at all out of the question. With the "big society" near the top of the government's agenda, the political discourse is very much leaning towards a return to localism and community-focused policy.
This is true of Labour, too -- the party's leadership campaign has been conducted in similar terms, the candidates repeatedly referring to their ability to "build a movement" and return control to the grass roots of the party. The clear front-runners, David and Ed Miliband, are no exception; both  have  referred to themselves as the preferred candidate of the party's grass roots.
With Britain facing an unfamiliar and unpredictable style of government, this could indeed be the high-water mark for groups such as the TPA. As well as left-leaning Liberal Democrats beginning to rebel , we have already begun to see more vocal dissent  from the right of the Tory party, especially as issues such as the referendum on AV move up the agenda.
And as the TPA chief executive, Matthew Elliott, is also leading  the "No to AV" campaign, his organisation is certainly going to be well placed to exploit growing unease on the right.
It seems more plausible than ever that if the TPA can add a swell of right-leaning popular support, the AV referendum and the local elections, both scheduled for May, could be the crucial turning point for this government.