With each new administration, the pool of people the president may lawfully kill expands. From Andrew P. Napolitano at lewrockwell.com:
Secretly and quietly, the Biden administration has continued to use the killing machine crafted by President George W. Bush, expanded by President Barack Obama and employed from time to time by President Donald Trump. These presidents have used drones and other unmanned missiles and projectiles to target persons in foreign countries with which the United States is not at war.
They have done this notwithstanding the prohibition of taking life, liberty or property from any person — not just any American, but any person — in the Constitution each has sworn to uphold, and they have done so pursuant to secret rules that they themselves have established for these killings.
Last week, 11 senators and 39 members of the House of Representatives — Democrats all — to their credit sent a harshly worded letter to President Joseph R. Biden asking him to stop the killings. As of this writing, he has not publicly replied.
Here is the backstory.
The purpose of the Bill of Rights — the first 10 amendments to the Constitution — is to protect personal liberty by restraining the government.
The Fifth Amendment prohibits killing persons, restraining liberty and taking property without due process; that means a jury trial at which the government must prove fault. Until President Abraham Lincoln waged war on half the country, the operative clause in the Fifth Amendment was understood to prohibit all federal killing without a declaration of war or due process.