Rockets: They've been around for, oh, 70 years. But just because they're senior citizens doesn't mean they're technologically decrepit. As North Korea's latest failed rocket test shows, launching a rocket into space is still, well, rocket science.

To successfully launch a rocket into space – a necessary achievement for creating the intercontinental ballistic missiles that North Korea wants and breathless American politicians baselessly fear they'll develop – you need expertise in lots of things. Lots of physics. Lots of safe handling of dangerous chemicals. And lots of experience.

To put it simply, successful rocket launches are "a really complex system using volatile chemicals and subject to extreme shock and vibration," explains Jeffrey Lewis, the director of the East Asia Nonproliferation Program at the Monterrey Institute. "The environment is so unforgiving that even small details are critical. As a result, tacit knowledge is important, even for low-level employees like welders and so forth. As a result, repetition and practice is essential."

As the world has seen, North Korea doesn't excel in repetition and practice. Its four rocket tests since 1998 have all been failures. And they've been failures in part because they haven't really been tests. They've been demonstrations – geopolitical statements of intent, rather than technological statements of experimentation.

Those aren't things you want to mix up. If you do, then the geopolitical statement you send is one of incompetence. The English-language internet greeted the North's latest failure with a mixture of derision and glee. So did the Obama administration.

"I guess the late founder of North Korea is disappointed. His birthday toy won't arrive on time," a senior U.S. official emails, along with a request to keep his name out of his jokes. "In fact, it won't arrive at all. And if it did, some major reassembly would be required."

In fairness, it's not just North Korea. The list of countries to have successfully launched a satellite into space is in the single digits. Still, North Korea's got some specific disadvantages.

"Not only are they short on money, but also expertise. Developing this technology requires expertise across a range of fields, from fluid dynamics to metallurgy to materials science to flight dynamics," says Brian Weeden, a former officer with the U.S. Air Force Space Command. "Countries that have been successful in this area all have extensive science, technology, engineering and mathematics programs to develop people with expertise in those fields.

"It seems North Korea is trying to shortcut this process by buying parts and technology from abroad," Weeden continues, "and slapping them together instead of taking the time and investing the resources to develop the proper foundations."

In particular, North Korea's short-range missile technology is based on work the Soviets did with their own rockets. But that's really difficult to scale up – as Pyongyang seems not to have figured out. "What they've tried to do is get a bigger rocket by strapping a bunch of Scuds and their variants together. It's not as easy as you'd think," says Victoria A. Samson, a rockets expert with the Secure World Foundation.

"They're clearly having trouble building multiple-stage rockets, which is what you need either to put a satellite up in space, or to build an [intercontinental ballistic missile] that can range, oh, say, the United States," Samson says. "Then you run into the problem of actually being able to aim the rocket, once you've launched it. I've always said that if North Korea ever got a rocket built that could technically reach the United States, they'd be lucky to hit any part of the continental Unites States, because they certainly wouldn't be able to guide it to its final destination."

Of course, all bets are off if the North Koreans decide a bespoke intercontinental ballistic missile is too hard and opt to go shopping. On the other hand, North Korea seems to like to export its missile technology. Documents revealed by WikiLeaks indicated that North Korea had passed on its missiles to Iran. That may not actually be true. But judging from North Korea's unbroken streak of failed launches, if Pyongyang really is sending missiles to Iran, that's a two-fer for Washington.