A firestorm erupted Tuesday over the letter by Sen. Tom Cotton, R-Ark. and 46 other Senators to Iran's Supreme Leader Ayatollah Khomeini, laying out their view of the ongoing negotiations regarding Iran's nuclear program. Critics of the letter started throwing around words like unprecedented, illegal, even treasonous.
The White House of course objects to members of Congress getting involved in foreign policy, which it sees as the president's exclusive domain. But the Cotton letter is part of the normal give and take of American politics, driven by the shared powers enshrined in the Constitution.