THE term “American exceptionalism” took on a bleak cast last week. A shooting at a Planned Parenthood clinic in Colorado that left three people dead and nine injured was swiftly followed by the massacre of 14 local health department workers in San Bernardino, California.

Given how many mass shooting incidents there have been this year — 353 and counting — politicians couldn’t avoid saying something about America and gun violence. In truth, mass shootings account for less than 5% of all gun homicides a year. But it is the assumption that the percentage is far higher that fuelled the outpouring of statements by Republican and Democratic presidential candidates on the merits of gun control.

There is a great deal to be said about the consequences of mass gun ownership. According to the Brady Foundation, almost 90 Americans die from gunshot wounds every day. The Republican contenders are against further restrictions, the Democrats are for, with Hillary Clinton intent on making a crackdown on firearms one of the defining platforms of her campaign. But the awful horrors of last week were not a consequence of weak laws or overzealous interpretations of the second-amendment right to bear arms. They were the result of terrorism.

The gun control issue has proved catastrophic for security because it has blinded American politicians to the link between deadly extremism and their own actions and rhetoric. There is no law against domestic terrorism in America. Until the 2001 Patriot Act it wasn’t even properly defined. It was only in October this year that the FBI established the Domestic Terrorism Counsel (DTC), an office dedicated to co-ordinating its investigations into homegrown terrorism. The bureau has yet to appoint someone to head the DTC.

Two days before the Colorado horror, pro-choice groups had delivered a petition to Loretta Lynch, the attorney general, asking the administration to label attacks on abortion clinics as domestic terrorism. That successive governments have refused to do so is one of the more disgusting examples of Washington hypocrisy. Since 1973, the year when abortion became legal, there have been 11 murders, 26 attempted murders and more than 200 bombings and arson attacks against clinics and the doctors who work in them. I’m not even going to list the number of acid attacks, death threats, vandalism, stalker incidents and neighbourhood harassment cases that are part of the daily arsenal of anti-abortion extremists. (The doctored videos put out this summer that purported to show Planned Parenthood clinics trafficking in baby parts just ratcheted everything up.)

While Democrats have remained inexcusably silent, some social conservatives have framed these attacks in language that all but praises the extremists for doing God’s work. They constantly invoke the spectre of Nazism and the Holocaust, of slavery and, of course, the “millions of murdered babies”. This is the kind of rhetoric that hate groups use to incite followers into action. Among the worst offenders is Senator Ted Cruz, a leading contender in the race for the Republican nomination, who boasted of his endorsement by the pro-life extremist group Operation Rescue. The pronouncements of Troy Newman, its head, reveal that he is a cheerleader for murder, saying that the US government has a responsibility to “deal with the blood-guilty [which] . . . involves executing convicted murderers, including abortionists, for their crimes”.

Not only has the pro-life camp succeeded in creating a safe space for anti-abortion criminality to flourish, it has also prevented any kind of rational discussion about domestic extremism.

In 2009 the Department of Homeland Security (DHS) published two reports on internal terrorism that included anti-abortion extremists. An outcry by various invested parties forced the DHS to withdraw the reports, leaving not just the issue of pro-life extremism, but all domestic extremism barely addressed by President Barack Obama. The analyst who wrote the report was eased out of the DHS; his team was disbanded.

Other studies conducted by the Brennan Centre of Justice and the Combating Terrorism Centre (CTC) at West Pointshow that white supremacists, anti-government militias and “sovereign citizen” groups have proliferated since 2008. The CTC has counted an average of 337 extremist attacks a year. By extremist it i s not referring to al-Qaeda or Isis, but to domestic attacks “by groups or individuals affiliated with far-right associations”.

This mixed bag of terrorists has also been responsible for the 2012 massacre at the Sikh temple in Wisconsin and the shooting of nine people during Bible study at a church in Charleston, South Carolina, in June this year.

A 2014 poll of 382 local and national crime departments revealed that 74% put anti-government extremism among the top three terrorist threats in their community. Only 39% cited Islamic extremism. More San Bernardinos may cause the latter percentage to rise. But whether or not jihadist-inspired violence increases, we are still left in a situation where black churchgoers aren’t safe and doctors are considered fair game.

America’s political class has to shoulder some of the blame. For years it refused to confront homegrown extremism. Now the country is simultaneously under attack from internal and external terrorism. What’s worse, there’s still no national agreement or plan of action to deal with the domestic threat. Nor will there be as long as extremists and their apologists get away with murder.