None of these three requirements was met to justify the use of military force in Syria. First, Congress had not declared war. Second, the administration stated it was not relying on the 2001 or 2002 AUMFs (which would not apply anyway) and there was no other congressional authorization. Third, there had been no attack on the United States or US armed forces before Trump’s missile strike. It thus violated the WPR.
Moreover, even if the military attack on Syria did not run afoul of the WPR, it violated the United Nations Charter, a treaty the United States has ratified, making it part of US law under the Supremacy Clause of the Constitution, which says treaties shall be the supreme law of the land.
Article 2(4) of the Charter says that states “shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state.”
The Charter only allows a military attack on another country when conducted in self-defense after an armed attack or if the Security Council has authorized it. Neither occurred in this case.
Syria had not attacked the United States or any other country before Trump directed the missile strike.
“The use of chemical weapons within Syria is not an armed attack on the United States,” according to Notre Dame law professor and international law expert Mary Ellen O’Connell.
Nor had the Council approved Trump’s attack. It therefore violated the Charter. In fact, Assad would have a valid self-defense claim, since the United States initiated an armed attack on Syria.
In his April 8, 2017, report to Congress, Trump claimed he ordered the missile strike to avert “a worsening of the region’s current humanitarian catastrophe.” So-called humanitarian intervention is not a settled norm of international law. To be lawful, military force can only be used in self-defense or with the blessing of the Security Council. Neither was present in this case.
It is critical that Americans know the administration’s purported legal rationale for the Tomahawk missile strike because Trump has launched illegal strikes, and may launch additional military attacks in the future.
A Dangerous Precedent for Attacks on North Korea?
As Kaine wrote in his letter to Tillerson,
“I am also concerned that this legal justification [in the secret memo] may now become precedent for additional executive unilateral military action, including this week’s U.S. airstrikes in Syria against pro-Assad forces or even an extremely risky ‘bloody nose’ strike against North Korea.”
Kaine was referring to the February 7 air and artillery strikes the US-led coalition mounted in Syria. And on February 10, the US-led coalition bombed a T-72 tank in Syria’s Euphrates River Valley.
The Wall Street Journal reported in January that the Trump administration is considering a preemptive “bloody nose” strike against North Korea: “React to some nuclear or missile test with a targeted strike against a North Korean facility to bloody Pyongyang’s nose and illustrate the high price the regime could pay for its behavior.”
Preemptive military attacks violate the UN Charter’s prohibition on the use of military force except in self-defense or with Security Council approval. In a February 5 letter, 18 senators informed Trump that he lacks the “legal authority” to conduct a preemptive military strike on North Korea. They cited “the risks of miscalculation and retaliation” and decried the administration’s removal of Victor Cha from consideration for US ambassador to South Korea, reportedly due to his disagreement with the “bloody nose” strategy.
Sen. Bob Corker (R-Tennessee), chairman of the Senate Foreign Relations Committee, said in October that Trump’s dangerous threats could put the United States “on a path to World War III.”