Continuing my efforts to demonstrate that a little knowledge of the law is a dangerous thing (and adding a superfluous Wald to the name of the AngryBear competent to discuss this) I wonder how and why Senators decided that the President must seek their advice and consent before performing any foreign policy (including for all I know officially expressing the wish that foreign heads of state have a happy birthday).
The phrase appears twice in The Constitution in Article II Section 2 describing the athority of the President.
He shall have Power, by and with the Advice and Consent of the Senate, to make Treaties, provided two thirds of the Senators present concur; and he shall nominate, and by and with the Advice and Consent of the Senate, shall appoint Ambassadors, other public Ministers and Consuls, Judges of the supreme Court, and all other Officers of the United States, whose Appointments are not herein otherwise provided for, and which shall be established by Law:
In the actual relevant text, advice and consent is required to make treaties and appoint ambassadors. There is nothing about involving the Senate in negotiations or even informing the senate about the progress of negotiations. There is no requirement that the US representative at the UN (usually called the ambassador to the UN but not so called by the UN) seek the advice and consent of the Senate before voting in the Security Council.
It is clear that under the constitution, relevant treaties (such as the convention establishing the United Nation) and current law, secretary of State Kerry does not need the advice and consent of the Senate to negotiate with foreign minister Zarif.
The possibly Logan act violating 47 non traitors didn’t even claim that negotiating without their participation is improper in their outrageous letter.
The argument appears to be “listen to me me meee” because I am bored with negotiating with even more insane representatives in the House to keep the government open.