Each of the following is an example of the Executive Branch as a source of law EXCEPT for which one?

Each of the following is an example of the Executive Branch as a source of law EXCEPT for which one?

President Truman$$s decision to seize the nation$$s steel mills to prevent a strike

President Clinton$$s decision not to support a bill introduced by Congressman Archer replacing the federal income tax with a national sales tax

President Carter$$s decision to enter into a treaty with the nation of Panama

President Johnson$$s decision to require government contractors to set out an affirmative action plan for the hiring and promotion of minorities and women