Surprise. She’s at it again. North Korean leader Kim Jong-un’s little sister, Kim Yo-jong, is rhetorically blasting away at the Americans and South Koreans in the run-up to their most intensive joint war games in five years.

Although Miss Kim may be losing out to Mr. Kim’s tween-aged daughter, Ju-ae, as his likely successor, the dictator’s sister is still valued for saying what he wants without putting his name on her colorful verbiage, as reported in English by Pyongyang’s Korean Central News Agency.

The focal point of her latest rhetorical outpouring is a South Korean report of a threat attributed to the commander of American forces in the Pacific, Admiral John Aquilino, to shoot down any intercontinental ballistic missile fired by the North Koreans.

Whether Admiral Aquilino made such a vow, as claimed in the South Korean press, is uncertain. Ms. Kim acknowledged the comment may have been “nothing but the puppet media’s trite wordplay,” but that didn’t stop her from responding that the Pacific “does not belong to the dominion of either the U.S. or Japan” and that the North was ready to take “overwhelming action.”

That Kim Yo-jong still serves as a useful voice for her brother shows her value even though he’s appearing regularly with his daughter, Ju-ae. It’s widely speculated that Kim Yo-jong may be tutoring the girl, whom Kim Jong-un has clearly selected as the favorite of his three children, including an older brother and a younger sibling, gender unknown.

Kim Yo-jong’s remarks were just the opening for what’s expected to be a steady torrent of North Korean rhetoric before and during the 10 days of joint American-South Korean exercises starting March 13. South Korea is expected to test-fire missiles — and might launch a satellite that could try out the gear for updated versions of its long-range missiles.

That was the suggestion in a KCNA report that North Korea might “finish preparations” for its “first military reconnaissance satellite by April.” The vice director of the North’s National Aerospace Development Administration, Pak Kyong-su, was quoted as saying NADA had “succeeded in developing a high-thrust engine for carrier rockets” for launching “various kinds of satellites.”

Kim Jong-un has yet to order what would be the North’s seventh underground nuclear test, as widely expected, but KCNA quoted a spokesman for the North’s foreign ministry as warning “the danger of a nuclear war on the Korean peninsula is turning from an imaginary stage due to a realistic one due to the irresponsible deeds of the U.S. and South Korea.” North Korea last staged a nuclear test in September 2017.