Image caption Campaigners claim right-wing groups such as Aryan Nations are on the rise

Did the election of Barack Obama as US president boost the growth of right-wing and so-called "hate groups"?

A curious thing happens when you walk down the street in Spokane, Washington, first thing in the morning. Complete strangers look you in the eye, and say, with a little smile: "Good morning."

It is that kind of a town; if not close-knit, then, compared to some of the other towns and cities in America, human in scale and friendly to strangers.

Which makes the attempted bombing here of a civil rights march in January all the more difficult to comprehend.

The man alleged to have left a rucksack filled with explosives and shrapnel - covered in rat poison so as to stop blood clotting - is Kevin Harpham, an Army veteran with an interest in neo-Nazi groups.

We live in a different world now - hate seems to be a widespread phenomenon Ozzie Knezovich, Spokane sheriff

The difficult truth for Spokane, for Washington State, for neighbouring Idaho and for all of the US, is that hate groups - anti-black, anti-Jew, neo-Nazi - are on the rise again.

And nearly everyone, including members of those groups, agrees that the election of Barack Obama has been a catalyst for the increase in support.

"I wouldn't say it surprises me," says Spokane's mayor Mary Verner, "though it is alarming to me".

"We are seeing a resurgence in hate groups because we are seeing democratic activity and empowered citizens who are not Anglo-Saxon Protestants."

There was the same sort of reaction from the local sheriff, Ozzie Knezovich, when he heard that a bomb had been left beside the route of the Martin Luther King Jr Day march.

"Surprised? No," he says. "We live in a different world now - hate seems to be a widespread phenomenon right now."

'Explosion' of groups

And there are ordinary citizens - and their children - who are at the receiving end of hate group activity in Washington and Idaho.

Image caption Barack Obama has faced repeated questions about his legitimacy as president

Rachel Dolezal, who teaches art and African-American studies, has been repeatedly harassed since word got out about what she taught.

Her homes - she has moved several times - have been broken into. Nooses have been left for her, and a swastika was left on the door of her workplace.

And she has acted to protect her son.

"I actually bought him a pair of earphones for the bus," she says, "because he hears the word 'nigger' every day.

"It seems things were kind of hush and sanitised and cleaned up, or something, and then Barack Obama just brought things to the surface that were already existent within people."

Hate groups and other groups on the far right - so-called Patriot groups which vow to resist the encroachments of the Federal government, and anti-immigrant nativist groups - are tracked by the Southern Poverty Law Centre (SPLC).

"In the fall (autumn) of 2008," says the director of the SPLC's Intelligence Project, Mark Potok, "we started to see an explosion in hate groups, but more generally in right-wing groups of general types."

Rise in requests

If Mark Potok wanted confirmation of his research, he could find it just across the border from Spokane, in the city of Coeur d'Alene, northern Idaho.

Sitting on his porch as the day fades into night is Jerald O'Brien, flanked by the flags of the Aryan Nations group and the Church of Jesus Christ-Christian.

Image caption Aryan Nations supporter Jerald O'Brien describes Jews as "the children of Satan"

Aryan Nations is a wildly anti-Jewish white separatist group. The faded plastic children's toys on the lawn seem more than a little incongruous.

Mr O'Brien insists he does not condone or encourage any acts of violence. He calls Jews "the children of Satan".

He accuses Barack Obama of being Jewish - he is not - and of not being a US citizen - he is. But he has cause to thank the president.

"The day after Barack Obama's election," he says, "my phone would not stop ringing. It was up to four or five a day asking for education and information."

Some will dismiss men such as Jerald O'Brien, and groups such as Aryan Nations, as "wackos" and "nut-jobs".

But Mark Potok is concerned.

"I think we are in a very similar period as we were in the run-up to the Oklahoma City bombing," he says, "as far as a bombing or an attack like that, whether that will come, we don't know.

"We are very close in numbers to the numbers we had at the very peak of the militia movement."

The trial of Kevin Harpham, accused of attempting to the bomb the Martin Luther King Jr Day march in Spokane, begins in August.

America's Own Extremists: The Militias Strike Back is on the BBC World Service from 0905 BST on Tuesday 5 July. You can also listen via the BBC iPlayer or download the podcast.