Maybe the end of a short attention span. The Rosenbergs helped Stalin obtain a nuclear bomb after world war 2 was over and the cold war was on. That was threatening the life of every American. Clearly a totally different case.
That is an excellent point and one which good and established governments should have as a capital offense. Still, it is NOT one that the US Constitution would permit. What was the law in the states in which the Rosenbergs operated?
We tried them in the wrong venue, or we need a change in the Constitution.
The Federal government has too many criminal laws -- the criminal codes under Federal jurisdiction should be either to the state in which the Federal power or authority is exercised, or to a territorial legislative body and/or governor, or to a military tribunal.