Obama has supplied aid and weapons to the Arab Brotherhood which has been defined as a terrorist organization and an enemy to the United States. Here is what the Constitution actually reads.
"Treason against the United States is defined as levying (making) war against the United States or giving aid or comfort (any help) to enemies of the United States. To convict a person of treason, there must be two witnesses who actually saw the person commit the traitorous act, or the accused person must confess (admit) to it in public court."
Anyone can look this up and is encouraged to. The accusations made here are common knowledge and were reported by various news agencies both main stream and private.