On 4/4/17, Syrian warplanes launched chemical weapons against rebels in a civil war battle.
On 4/6/2017, the US Navy fired 59 Tomahawk missiles from the USS Porter and the USS Ross (destroyers located in the Mediterranean Sea) against an airfield in Syria.
On 4/9/2017, the US Navy sent the Carl Vinson strike group (including an aircraft carrier) to the Korean peninsula.
On 4/10/2017, China deployed approximately 150,000 troops to its North Korean border.
On 4/11/2017, a US-led coalition mistakenly killed 18 members of an allied Syrian force with a drone strike in the south of Tabqa, Syria.
On 4/13/2017, in its war against ISIS, the US dropped the Massive Ordinance Air Blast Bomb on a tunnel infrastructure in the Nangarhar province of Afghanistan.
On 4/15/2017, North Korea held a military parade; part of the parade included (what military analysts believe to be) intercontinental ballistic missiles.