This is from David Kopel at the Volokh Conspiracy:
According to The Korea Times, the Obama administration has blocked efforts by the South Korean government to sell over a hundred thousand surplus M1 Garand and Carbine rifles into the United States market. These self-loading were rifles introduced in 1926 and 1941. As rifles, they are especially well-suited to community defense in an emergency, as in the cases of community defense following Hurricane Katrina in 2005 and Hurricane Andrew in 1992. Along with AR-15 type rifles, the M1 rifles are the quintessential firearms of responsible citizenship, precisely the type of firearms which civic responsibility organizations such as the Appleseed Project teach people how to use.
According to a South Korean official, “The U.S. insisted that imports of the aging rifles could cause problems such as firearm accidents. It was also worried the weapons could be smuggled to terrorists, gangs or other people with bad intentions.”
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Legally, it is indisputable that the guns are importable. Being over 50 years old, the rifles are automatically “Curios and Relics” according to federal law. 27 CFR section 478.11. Accordingly, they are by statutory definition importable. 18 USC section 925 (e)(1). Notwithstanding the law, the Obama administration has the ability to pressure the South Korean government to block the sale of the guns.