North Korea’s successful launch of an intercontinental ballistic missile (ICBM), called a “package of gifts” for Independence Day by their leader Kim Jong Un, prompted a swift response by South Korea and the U.S. The two nations test-fired missiles of their own of the East coast of South Korea according to the Washington Post Wednesday. The gesture was meant to posture strength.

The launch was North Korea’s first successful test of an ICBM, and the fear is that North Korea will eventually be able to arm an ICBM with a nuclear weapon and strike the U.S. The July 4 ICBM test was North Korea’s farthest missile test.

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David Wright, co-director of the Union of Concerned Scientists, wrote in a blog post that judging from reports, a missile similar to the one tested could not reach the continental United States but could possibly reach Alaska.

“(Kim) stressed that (North Korea) would neither put its nukes and ballistic rockets on the table of negotiations in any case nor flinch even an inch from the road of bolstering the nuclear force chosen by itself unless the U.S. hostile policy and nuclear threat to (North Korea ) are definitely terminated,” read a statement Wednesday from the Korean Central News Agency, North Korea’s state media wing. “(Kim) with a broad smile on his face, told officials, scientists and technicians that the U.S. would be displeased to witness North Korea’s strategic option as it was given a ‘package of gifts.’”

The U.S. is weighing its options for the next step.

North Korea Missile
North Korean leader Kim Jong Un inspects the intercontinental ballistic missile Hwasong-14 in this undated photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang July 5, 2017. KCNA/REUTERS

“Self-restraint, which is a choice, is all that separates armistice and war,” cautioned General Vincent Brooks, the U.S. commander of soldiers based in South Korea, in a dual statement with his South Korean counterpart. “We are able to change our choice when so ordered by our alliance national leaders … “it would be a grave mistake for anyone to believe anything to the contrary.”

President Donald Trump, who has leaned on China to do more economically curtail North Korea, expressed his frustrations via Twitter.

“Trade between China and North Korea grew almost 40% in the first quarter. So much for China working with us - but we had to give it a try!” the president wrote Wednesday.

Last week the U.S. imposed sanctions on Chinese individuals and businesses that work with North Korea, whose biggest trading partner is China.

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Trump has said he is pivoting away from Barack Obama’s policy of “strategic patience” with North Korea. The U.S. doesn’t have official diplomatic relations with the country.

“Testing an ICBM represents a new escalation of the threat to the United States, our allies and partners, the region, and the world," said Secretary of State Rex Tillerson in a statement.