The launch appears to violate U.N. Security Council resolutions that ban North Korean ballistic missile activity.
The office of South Korean President Moon Jae-in said it is "very concerned" the North Korean missile test violates the spirit of the inter-Korean agreements.
But U.S. President Donald Trump and other U.S. officials quickly suggested the test was not very important. They said the North did not violate its own promise to stop tests of intercontinental ballistic missiles, or long-range ballistic missiles. However, some experts warn that position could frighten U.S. allies because short-range weapons could still hit South Korea and Japan.
North still upset about exercises
Robert Carlin is a North Korea scholar writing for the website 38 North. He says the North Korean test was probably a way to show anger toward the South Korean government for continuing joint military exercises with U.S. forces. Last month, Kim called the exercises "hostile acts."
North and South Korea did agree last April to stop "all hostile acts" against each other and eliminate the "danger of war." But they never signed an agreement to stop military exercises completely, and drills have continued on both sides.
North Korea also blames Moon for not acting on the inter-Korean agreements reached during three meetings over the past year. However, U.S. and international trade limits have prevented Moon from following through on many parts of the agreements.
Any time, any place, we can talk
The North Korean weapon launch puts additional pressure on Moon. His public approval rating was very high after his first meeting with Kim. Now it is half of what it was.
Adding to Moon's problems, South Korea's economy unexpectedly lost value in the first quarter of 2019.
A growing number of South Koreans oppose his contact with the North. They see it as unexperienced and unsuccessful.
Moon still wants to work with the North. He said last month he would hold a fourth top-level meeting with Kim "any time, any place."
I'm Jill Robbins.