Washington Post blogger Jennifer Rubin incorrectly wrote that Sen. Harry Reid (D-NV) is proposing to “ban explosive powder” as a response to the Boston Marathon bombings when in fact Reid has proposed requiring a criminal background check for individuals who buy explosive powder.

The Senate proposal, originally sponsored by Sen. Frank Lautenberg (D-NJ), but being shepherded by Reid in his absence, would require a background check to “purchase black powder, black powder substitute, or smokeless powder, in any quantity.” Furthermore the legislation would allow the Attorney General to stop explosives sales to suspected terrorists. Under current law inclusion on the terrorist watch list alone does not prohibit individuals from buying explosives or firearms.

While Rubin's apparent aim was to make Reid's response to the Boston bombings seem ridiculous -- explosive powder has many legitimate uses -- explosive powder is a common component in domestic bombings. Furthermore, because of lobbying by the National Rifle Association, it is currently legal to purchase up to 50 pounds of black or smokeless powder without undergoing a background check.

Decades before the Boston bombings -- where the perpetrators reportedly may have used black or smokeless powder -- explosive powder has been known to be regularly employed by domestic bombers. According to a 1980 report issued by the Office of Technology Assessment, a now defunct office of Congress, in incidents involving both successfully detonated and undetonated bombs, “black and smokeless powders and cap sensitive high explosives all occur with high frequency.” A 2005 report from the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) found that “because black powder is relatively inexpensive (between $5 and $15 per pound), it is the most common explosive used in pipe bombs.” The report also found that explosive powders were present in the most fatal of bombings between 2002 and 2004:

According to National Repository data, 8 people were killed and 49 people were injured by explosives from January 2002 through December 2004. Explosive powders, which may be obtained legally in quantities up to 50 pounds without a license or permit, were the largest cause of deaths and injuries. Over 50 percent of those killed and injured during this period were victims of explosive devices containing black powder. Twenty-five percent of those injured were victims of improvised explosives devices, many of which containing common chemicals.

Still the NRA has spent decades lobbying against the regulation of black and smokeless powder -- which can be components of gunpowder -- and is largely responsible for the current background check exemption for purchasers of up to 50 pounds of explosive powder.

While most individuals wishing to procure explosives must register with the ATF and submit to background checks through the National Instant Criminal Background Check System (NICS), the NRA has carved out exemptions based on the claim that a background check would unduly interfere with hobbyists who use black powder for antique firearms or smokeless powder to reload spent ammunition.

As detailed in an April report from the Violence Policy Center, the Nixon administration urged Congress in 1970 to assert increased regulatory control over explosives after a spate of domestic bombings. Because of successful lobbying by the NRA, the resulting legislation was amended to exempt most smokeless powder and up to five pounds of black powder from the federal government's regulatory authority. Three years later, the NRA successfully lobbied to increase the exemption to 50 pounds, despite opposition from the ATF and the Department of Justice. This exemption exists to this day, and was left intact by the Safe Explosives Act of 2002 which mandated a background check for “any person who transports, ships, causes to be transported, or receives explosives.” In 2012, NICS reported that that out of 148,856 background checks for explosives, 3,077 were denied.

Beyond dismissing a legitimate proposal that addresses the circumstances of the Boston bombings, Rubin also erroneously suggests -- albeit sarcastically -- that “maybe if we just passed background checks for guns, Islamist radicals would not set off bombs in public.” Not only is this is a nonsensical argument that no one is making, Rubin is ignoring the aims of the expanded background check proposal that was recently blocked by a coalition of largely Republican senators.

The Manchin-Toomey amendment would have expanded background checks to firearms sales that occurred at gun shows or over the Internet. While the aim was to make it harder for prohibited individuals to obtain a firearm by expanding the universe of sales that would require a background check, the proposal would also affect ways in which terrorists have obtained weapons.

According to a 2001 New York Times article, affiliates of Hezbollah and the Irish Republican Army have been caught using gun shows to obtain weaponry. An Al Qaeda spokesperson urged followers to exploit private sales without background checks at gun shows to obtain firearms. Gun shows have also been linked to narcoterrorism, with the ATF singling out private transactions that take place at these events as a source for weapons obtained by Mexican drug cartels.