The first time North Korea tested its submarine missile platform, it went so poorly that they had to photoshop a “success” photo. The second time, the missile cleared the surface but failed to do much more. This week, however, their sub-launched missile managed to travel 300 miles — far enough to worry and anger Japan and South Korea:

North Korea fired a submarine-launched missile on Wednesday that flew about 500 km (311 miles) towards Japan, a show of improving technological capability for the isolated country that has conducted a series of launches in defiance of UN sanctions.

Having the ability to fire a missile from a submarine could help North Korea evade a new anti-missile system planned for South Korea and pose a threat even if nuclear-armed North Korea’s land-based arsenal was destroyed, experts said. …

Jeffrey Lewis of the California-based Middlebury Institute of International Studies said the test appeared to be a success.

“We don’t know the full range, but 500 km is either full range or a full range on a lofted trajectory. Either way, that missile works.”

Lewis joins South Korean analysts in suggesting that the test didn’t allow for the missile’s full range. The higher angle of the launch shortened it by about half, according to Reuters’ report, and that its full range would have been 620 miles. To put that in perspective, Honshu (the main island of Japan) is about 145 miles wide at its peak. In fact, it’s only 810 miles long, which means that a North Korean submarine could potentially hit any point in Japan from almost any position around it.

Or to put it in another context: A sub off the West Coast could theoretically launch a missile that could hit targets as far into the US as Phoenix, Las Vegas, and Boise. The range on the East Coast would put targets in as far as Cincinnati, Buffalo, Atlanta, and possibly Detroit. That’s not exactly a new concept for the US, as Russian boomers had even greater capabilities; we’ve lived under that threat for decades. The difference is that the Russians have been (relatively) rational opponents, who have a lot to lose in that kind of exchange and have no real use for that level of destruction. The Kim regime, on the other hand, operates on a less-rational basis and has much less to lose.

Reuters quotes Joshua Pollack, editor of the U.S.-based Nonproliferation Review, as saying this was as much about prestige and respect as it was about acquiring the military strength to carry out the attack. That may well be true, but … does anyone want to bet on that? They are working on miniaturizing nuclear warheads to fit onto missiles like the one launched this week, and are likely developing longer-range submarines to deploy them when they succeed in their nuclear-warhead development. They may not deserve respect, but they are becoming an existential threat to key American allies in the region and no small threat to us, too. Toying with the UN and the six-nation debate society hasn’t done anything to curb that threat. It might be time for a new approach.