For instance, during an April concert celebrating North Korea's founding father and Kim's grandfather, Kim Il Sung, the country unveiled a video that showed its missiles blowing up San Francisco. If realized, it would be her first trip to Japan since she took power in July past year.
A picture released by Korean Central News Agency showing North Korea's intercontinental ballistic missile (ICBM) Hwasong-14 being launched at an undisclosed place in North Korea.
Abe and May last met in early July on the sidelines of the Group of 20 summit in Hamburg, Germany. Both Japan and the United States have ships equipped with SM-3 missiles designed for ballistic missile defense. It also has a spotty record, although its most recent test, in May, was a success.
The Patriot first gained popularity for success against Iraq's Scud missiles during the first Gulf War.
A missile is a guided weapon, unlike a rocket, and a ballistic missile is one that can move along a suborbital trajectory, skimming the Earth's atmosphere to travel much further than normal missiles.
According to the analysis, the Hwasong-14 missiles tested in July were engineered to reach a very high altitude, but may lack the power to carry a heavy nuclear payload across the ocean to the US.
Guam is home to a USA air base, a Navy installation, a Coast Guard group and roughly 6,000 United States military personnel.
Japan's missile defence scheme employs Maritime Self-Defence Force Aegis destroyers to shoot down airborne missiles, and the PAC-3 system operated by the Air Self-Defence Force to counter missiles that evade Aegis interceptors. "So they still won't tell you if it works in a real-world situation".
In a separate statement attached to the article, Postol, an expert in ballistic missile defense, stated that while existing ballistic missile defenses "will never work reliably", there is still time to develop a defense system with available USA technology.
But Sullivan said the USA needs "belts and suspenders" when it comes to missile defense - redundancy.
Laura Grego, a senior scientist at the Union of Concerned Scientists, said the Air Force looked into using a laser that's mounted in a Boeing 747 - to shoot down missiles in their boost phase - but the plan was scrapped for being too expensive.
"If one of those options is a pre-emptive war on the Korean Peninsula launched by the US, that would require authorization from Congress. Article I of the Constitution, in my view, makes this clear", Sullivan said. "The U.S. came here because I think they wanted the land and they helped us out with the Japanese, because I think they wanted the land. So China and Russian Federation could just move launchpads into the interior of the country so you'll never get close enough".