Remember in 2009, right at the start of the Obama era, when then-Secretary of Department of Homeland Security Janet Napolitano issued a report (PDF) entitled: “Right-wing Extremism: Current Economic and Political Climate Fueling Resurgence in Radicalization and Recruitment”? The report was truly prescient. It alerted us to the rise of right-wing extremism, such as from white supremacist groups, and warned that unchecked, it could lead to violence.

How did Republicans respond? They went ballistic attacking the report. John Boehner was especially upset that Napolitano would use the term “terrorist” to “describe American citizens who disagree with the direction Washington Democrats are taking our nation,” adding, “using such broad-based generalizations about the American people is simply outrageous.”

Well, what have we seen since 2010? An explosion in the number of hate groups and a rash of domestic terrorist acts committed by those very right-wing groups Napolitano warned us about. Per the Southern Poverty Law Center, since 2010, there have been 32 instances of terrorism by far-right groups—that equals eight attacks per year. (Of course, citing the SPLC won’t move many on the right because they continually tell me on Twitter that the SPLC is biased. They’re correct, the SPLC is biased. Against bigotry.)

The attacks include a plot in 2011 by members of a Georgia militia group to bomb a federal building and release deadly ricin in Atlanta; an attack by a white supremacist on a Sikh temple in Wisconsin that killed six people; another white supremacist planting bombs at a Martin Luther King parade in Seattle; and numerous plots against or actual killings of law enforcement officers. And this list doesn’t even include the anti-government LAX gunman who killed a TSA officer and wounded another in November 2013, or the attack we saw this past weekend by Jerad and Amanda Miller, who executed two Las Vegas policemen and then tossed the Gadsden flag used by the Tea Party onto the dead officers’ bodies.

So how have Republicans responded to the rise of attacks by right-wing groups? By ignoring it and keeping their focus on foreign terrorists and Muslim-Americans. Perhaps the Republican members of Congress would find it instructive to reread the oath they took upon being sworn into office that provides in part: “I do solemnly swear to defend the United States…against all enemies, foreign and domestic.”

I’m sure they are fully aware of these words. The actual reason Republicans won’t investigate right-wing extremists is that it would not only anger their base, it would actually indict some parts of it. Let’s be honest: In a time when establishment Republicans are concerned about getting challenged in primaries by more conservative Tea Party types, calling for hearings to investigate right-wing organizations could be political suicide.

So instead, in 2011 and 2012 we saw Rep. Peter King hold five sets of hearings about the radicalization of Muslims when he was chair of the House Homeland Security Committee. I attended the first of these hearings and listened as Democratic members of the committee urged King to broaden his investigation to look at radicalization of Americans regardless of faith. They cited studies warning of a record number of right-wing hate groups and resurgence of anti-government chatter. But King wouldn’t have any of it.

We have seen similar tactics by Republicans in state legislatures. Instead of focusing on potential far-right groups in their state, they have passed laws intended to demonize Muslims because it plays to their base. In fact, just last month in Florida, an anti-sharia measure was signed into law by Gov. Rick Scott even though supporters admitted there hadn’t been even one instance of Muslims in Florida trying to impose Islamic law. Yet, in Florida there has been a documented upsurge in the Ku Klux Klan, with the group now boasting more than 1,000 members.

And some Republican elected officials have even implicitly given their blessings to the right-wing view that weapons may be needed to fight off an overreaching federal government. We saw this during the recent standoff between Nevada rancher Cliven Bundy and federal officers. Rand Paul and other GOP officials praised Bundy with full knowledge that there was in essence an armed militia of private citizens who had their guns trained on federal officers.

The threat of right-wing domestic terrorism is very real. In fact, just last week, the Department of Justice announced that it was reviving its domestic terrorism taskforce. As Attorney General Eric Holder explained, we must be vigilant in protecting Americans against the “danger we face from individuals within our own borders who may be motivated by a variety of other causes from anti-government animus to racial prejudice.”

It’s time that the GOP join in the fight against the threats posed to our nation by right-wing extremists. True, this could cause them problems with parts of their own political base, but saving American lives must trump politics.

In a perfect world, the GOP would address the threats posed by these extremists with the same zeal they’re investigating the “truth” surrounding Benghazi. But they won’t. The hard truth is that the GOP can’t lose any of its shrinking base by alienating the lunatic fringe and their supporters, from the Ted Nugents to the Cliven Bundys to the white supremacists. You see, what we view as radicals, the GOP views as their last, best hope.