With the stroke of a pen, a war of words oozing with condescension has erupted between Iran's foreign minister and a group of U.S. senators.
The row was sparked when 47 Republican members of Congress sent a letter dated March 9 to Iran's leaders schooling them on particularities of the U.S. constitutional system that the Iranians "may not fully understand" and "should seriously consider" as nuclear negotiations progress.
The senators noted that any treaty worked out between the United States and Iran would require ratification by a two-thirds vote in the Senate. Anything short of that, they wrote, would be considered a mere executive agreement between U.S. President Barack Obama and Iranian Supreme Leader Ayatollah Ali Khamenei. Such an agreement, they warned, could be revoked by the next agreement "with the stroke of a pen" or modified by future Congresses "at any time."
The senators signed off by saying: "We hope this letter enriches your knowledge of our constitutional system and promotes mutual understanding and clarity as nuclear negotiations progress."
To ensure that the message was not lost in translation, the writer of the letter, Senator Tom Cotton (Arkansas), sent a tweet out to Iran's Foreign Minister Mohammad Javad Zarif to alert him that the letter was available in Persian.
Zarif, who was educated in the United States and speaks fluent English, wasted little time firing back.
In a response reported by Iranian media and posted on the website of Iran's Foreign Ministry on March 9, Zarif wrote in the hope that his comments "may enrich the knowledge of the authors to recognize that according to international law Congress may not 'modify the terms of the agreement at any time' as they claim and if Congress adopts any measure to impede its implementation it will have committed a material breach of U.S. obligations."
He suggested, in the words of the Iranian Students News Agency (ISNA), that the senators "not only do not understand international law, but are not fully cognizant of the nuances of their own constitution."
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Denouncing the letter as having "no legal value" and being a "propaganda ploy," Zarif noted that the "world is not the United States, and the conduct of inter-state relations is governed by international law, and not by US domestic law."
Again in the words of ISNA, Zarif "expressed astonishment that some members of the U.S. Congress find it appropriate to write to leaders of another country against their own president and administration."
The letter-writing row sparked a skirmish on the domestic front in the United States as well.
Responding to the letter sent by the Senators -- an act described in some media as traitorous ...
... U.S. President Obama was diplomatic.
"I think it is somewhat ironic to see some members of Congress wanting to make common cause with the hard-liners in Iran," he told reporters on March 9. "It's an unusual coalition."
He then shifted the focus to the effort to "seeing whether we can work out a deal or not" and expressed confidence that "if we do" his administration would be able to implement it.
Vice President Joe Biden was terse in his response, saying in a statement on March 9 that "the decision to undercut our president and circumvent our constitutional system offends me as a matter of principle."
That, in turn, was met by a response by Cotton, who questioned Biden's decision making record and defended the senators' letter on March 10.
"We're making sure that Iran's leaders understand that if Congress doesn't approve a deal, Congress won't accept a deal," he told MSNBC.