Wong Maye-E, Ahn Young-joon / AP

North Korea is quickly becoming President Trump's biggest challenge, but it long predates the new administration. Below is a timeline of how the U.S. and its allies have tried to push North Korea away from building a nuclear arsenal.

October 2006: North Korea claimed to have conducted first nuclear test. The United Nations responded with sanctions.

2007-2008: After start-stop attempts at a deal, the UN backed off sanctions on North Korea in exchange for stripping down its nuclear program.

May 2009: North Korea conducted second nuclear test, received new sanctions.

February 2013: North Korea conducted a third nuclear test, and received more sanctions.

2015: Former President Obama stepped up U.S. cyber attacks on North Korea's missile programs.

2016: North Korea held its 4th and 5th nuclear tests, and conducted more than 14 rounds of ballistic-missile tests — almost all of which failed — and fired 30 different rockets, Business Insider counted up.

November 2016: WSJ reported that the Obama administration told the Trump administration that North Korea was the biggest international threat to the U.S.

March 1, 2017: South Korea and the U.S. held a military exercise — "Foal Eagle"— together.

March 6: North Korea fired four ballistic missiles into the sea near Japan.

March 15: The U.S. holds a flight test of a nuclear bomb.

March 22: North Korea had another failed missile launch on its east coast.

Sunday, April 9: The U.S. deployed a Navy strike group to the waters off the Korean Peninsula, which included two guided-missile destroyers, one guided-missile cruiser, and an aircraft carrier.

Tuesday, April 11: Trump tweeted: "North Korea is looking for trouble. If China decides to help, that would be great. If not, we will solve the problem without them! U.S.A."

Wednesday, April 12: Seemingly in response to the U.S. strike group, satellite images suggested North Korea was going to conduct its sixth nuclear test.

Thursday, April 13: The US placed two Tomahawk cruise missiles carriers in the area — one of them 300 miles from the North Korean nuclear site and NBC reported that the U.S. was preparing to launch a preemptive strike on North Korea. Officials then told AP that those reports were false.

Saturday, April 15: In the morning, North Korea held a military parade, showing off their new ballistic missiles. In the evening, North Korea launched a missile test, which failed.

Sunday, April 16: Mike Pence speaks in the demilitarized zone between North and South Korea. "North Korea would do well not to test [Trump's] resolve ... all options are on the table ... the era of strategic patience is over."

Go deeper

Updated 25 mins ago - Politics & Policy

Coronavirus dashboard

Illustration: Annelise Capossela/Axios

  1. Global: Total confirmed cases as of 7:30 p.m. ET: 19,971,615 — Total deaths: 733,103 — Total recoveries — 12,200,847Map.
  2. U.S.: Total confirmed cases as of 7:30 p.m. ET: 5,079,941 — Total deaths: 163,331 — Total recoveries: 1,670,755 — Total tests: 62,513,174Map.
  3. Politics: Trump claims he would have not called for Obama to resign over 160,000 virus deathsHouse will not hold votes until Sept. 14 unless stimulus deal is reached.
  4. Business: Richer Americans are more comfortable eating out.
  5. Public health: A dual coronavirus and flu threat is set to deliver a winter from hellAt least 48 local public health leaders have quit or been fired during pandemic.
  6. Sports: The cost of kids losing gym class — College football is on the brink.
  7. World: Europe's CDC recommends new restrictions amid "true resurgence in cases."

Trump says G7 summit will be delayed until after the election

President Trump told reporters on Monday that he wants to delay the G7 summit until after November's election and implied that the decision had already been made.

The big picture: Plans for the summit have already been scrapped multiple times, with proposed venues moving from the Trump National Doral resort in Miami to Camp David. In May, Trump postponed the in-person event in Washington, D.C. to September.

Trump whisked out of press briefing after shooting outside White House

President Trump was escorted out of a coronavirus press briefing by a Secret Service agent on Monday after law enforcement reportedly shot an armed suspect outside of the White House.

The state of play: Trump returned to the podium approximately ten minutes later and informed reporters of the news. He said the suspect has been taken to the hospital, but was unable to provide more details and said Secret Service may give a briefing later.