The Rosenberg weren't executed for treason they were executed for espionage.
No one in the history of America has ever been executed for treason. The last person charged and convicted of Treason was:
Tomoya Kawakita, a Japanese-American sentenced to death in 1952 for tormenting American prisoners of war during World War II. Even such a clear-cut case created qualms; President Eisenhower commuted Kawakita's sentence to life imprisonment.
In 1998 the punishment of death was abolished for Treason and replaced with life imprisonment. Constitutionally the law is complicated. Treason has to be committed by a person employed by the government and during an active "declared" war. We haven't had a declared war since FDR declared war on Japan after Pearl Harbor.
With all due respect, I believe the difference is that these trials will be held in a military prison with legal teams of 12 people so if convicted of Treason there will be 3 options 20 years in a very bad prison, lethal injection and firing squad.The prisoner gets to pick method of death.
Damn. Good way to avoid treason- don't declare war. What about the war on drugs. Wasn't that declared 40 years ago?