There are whole libraries filled with the laws of this country but only one crime that was of such importance that it was specifically placed into the United States Constitution, the crime is treason and the reason for this prominence wasn't because the founder intended it be used, but rather to constrain its use under the most rigid checks. Treason was a charge that could be levied in other countries for the simple matter of offending a king or potentate. Call the queen fat and your head was on a pole after somebody ripped out your insides while you watched. Not only could a person be called traitor, but their unborn grandchildren would carry the stigma of blood guilt as well.
The founding fathers wanted it to be a complete and unmitigated pain in the backside to make a charge of treason, so they codified it in Article III Section 3:
Treason against the United States, shall consist only in levying War against them, or in adhering to their Enemies, giving them Aid and Comfort. No Person shall be convicted of Treason unless on the Testimony of two Witnesses to the same overt Act, or on Confession in open Court.
The Congress shall have Power to declare the Punishment of Treason, but no Attainder of Treason shall work Corruption of Blood, or Forfeiture except during the Life of the Person attainted.
- Governor Thomas Dorr, convicted of treason against the state of Rhode Island for leading the Dorr Rebellion against the state of Rhode Island in 1844, he was released in 1845, his civil rights were restored in 1851 and the verdict ultimately annulled 1854.
- John Brown, convicted of and hung for treason against the Commonwealth of Virginia in 1859 following his raid on Harper’s Ferry as an act of armed insurrection, intending to create a slave revolution in the south.
- Aaron Dwight Stevens, took part in John Brown's raid and was also convicted of and executed for treason in 1859.
- Robert Henry Best, convicted of treason as an American broadcaster of Nazi propaganda during World War II. He was convicted in 1948 of treason and sentenced to life imprisonment.
- Iva Toguri D'Aquino, was tried and convicted of treason after WWII as "Tokyo Rose," a famous or infamous propaganda broadcaster, she was pardoned by President Gerald Ford when it came to light that she was convicted after a thoroughly tainted investigation and trial by a kangaroo court.
- Mildred Gillars was also tried and convicted of treason after WWII as "Axis Sally" and served 12 years of a 10-30 year sentence.
- Martin James Monti, a United States Army Air Force pilot convicted of treason for stealing P-38 fighter and defecting to german and joining the Waffen SS, he served a 25-year sentence.
- Tomoya Kawakita, held dual US and Japanese citizenship, he was charged and convicted of torturing American POWs and sentenced to death, President Eisenhower commuted this sentence to life imprisonment and Kennedy ordered hi released to Japan and barred his return.
That's the whole list. The entire list of those convicted of treason, eight in all, six for treason against the United States (one executed), two for treason against a state, Rhode Island and Virginia (one executed), the exact number of trials conducted for treason is harder to pin down, the closes I've been able to find is 40 prosecutions for treason in United States History, with a very few prosecutions covering more than one defendant. The number of convictions would have probably been higher but George Washington pardoned all convicted in the Whiskey Rebellion Trial and Andrew Johnson issued a blanket pardon to all of those indicted (including Jefferson Davis and Robert E. Lee) before they could be brought to trial.
It's a daunting things to attempt to try one of treason in the US, Benedict Arnold was never tried. Julius and Ethel Rosenberg, Jonathon Pollard John Walker and family, all convicted, but of espionage not treason. John Walker Lindh was convicted of conspiracy to murder US nationals, again, not treason. There has only been one person charged for treason since 1952, Adam Yahiye Gadahn, charged in 1996 for his part in making al-Qaeda propaganda, stay tuned, this is still in the legal mill somewhere.
Congress, as directed by the Constitution, passed United States Code at 18 U.S.C. § 2381: "whoever, owing allegiance to the United States, levies war against them or adheres to their enemies, giving them aid and comfort within the United States or elsewhere, is guilty of treason and shall suffer death, or shall be imprisoned not less than five years and fined under this title but not less than $10,000; and shall be incapable of holding any office under the United States." Notice how tightly that's written?
There is a high bar for charging a person with treason, and higher bar to convict (roughly 80% of prosecutions failed so far), and a really high bar to actually hold a person for their full sentence. This is the way it should be, historically treason charges have been tossed around far too lightly, to the point where people really don't seem to have any idea of what it is under US law. Roughly 40 trials and only 8 convictions since the constitution was ratified and the last trial in 1952, and that's as it should be, lest we fall into the cesspool of the history of the "Old World" where the charge was used with complete negligence, often on royal whim.