North Korea’s July 4 launch. Getty Images

On Saturday, North Koreans will celebrate the anniversary of their country's founding, and experts think the country may mark the holiday with a full-range test of an intercontinental ballistic missile.

South Korean media earlier this week reported that a North Korean ICBM appeared to be on the move, and CNN cited the South Korean prime minister on Thursday as saying that "some believe" a launch Saturday was possible.

Also this week, North Korea said the US could expect more "gift packages" in the form of further missile testing. With only two successful tests on record, North Korea's latest ICBM is in need of further trials.

But firing a ballistic missile thousands of miles across the globe could have disastrous consequences if not executed properly.

North Korea fired a missile over Japan in late August, and geography dictates that Pyongyang will most likely have to do so again to complete a full-range ICBM test.

An unannounced missile heading toward the US mainland from North Korea could cause a nuclear retaliation, so Pyongyang would most likely try to aim the missile elsewhere.

Possible trajectories may send the missile south toward the pole or into the Pacific south of the US. Even unarmed, the missile's reentry vehicle would pose a huge threat to maritime life and traffic as it blazes through the atmosphere at many times the speed of sound.

But there's no guarantee the launch would be unarmed. In 1966, as the US and the outside world doubted China could build a functional nuclear-armed ICBM without outside help, Beijing launched a missile at full range with a nuclear payload.

North Korea released photos of Kim Jong Un touring a missile plant as if to prove doubters wrong. Reuters / KCNA

North Korea faces similar scrutiny today, with many doubting its nuclear and missile technology. Media releases from North Korea often seem intent on proving doubters wrong, and the country’s tests sometimes seem designed to demonstrate previously unattributed capabilities.

Detonating a nuclear device in international waters, even without killing someone, would cause an ecological disaster with a lasting effect on the environment. Such a move would also draw massive condemnation by the international community.

But it would demonstrate beyond a doubt that North Korea's long-range nuclear threat is real, and it would stress the US-South Korean alliance as never before, which fits right into Pyongyang's playbook.