A group of 47 Republican senators has released an open letter to Iran in a bid to disrupt the Obama administration’s attempts at a nuclear deal. The letter was spearheaded by Arkansas Republican Sen. Tom Cotton and signed by a number of potential 2016 presidential hopefuls, including Senators Marco Rubio, Ted Cruz and Rand Paul. It reads in part: “we will consider any agreement regarding your nuclear-weapons program that is not approved by the Congress as nothing more than an executive agreement between President Obama and Ayatollah Khamenei.” Iran’s foreign minister, Mohammad Javad Zarif, dismissed the letter as “mostly a propaganda ploy,” calling the tactics “unprecedented in diplomatic history.” President Obama criticized the Republicans for aligning themselves with hardline critics of the nuclear talks in Iran.

President Obama: “I think it’s somewhat ironic to see some members of Congress wanting to make common cause with the hardliners in Iran. It’s an unusual coalition. I think what we’re going to focus on right now is actually seeing whether we can get a deal or not. And once we do, then we’ll — if we do, then we’ll be able to make the case to the American people, and I’m confident we’ll be able to implement it.”

Secretary of State John Kerry returns to Switzerland Sunday in a bid to reach a nuclear deal before a March 31 deadline.

President Obama has declared Venezuela a threat to national security and slapped seven top officials with sanctions amid the worst diplomatic flare-up of the past two years. The sanctions target leaders of security forces involved in violence last year, which left dozens of people dead from both sides of Venezuela’s political divide. The White House said it was targeting human rights abuses and corruption, not Venezuela’s rich oil sector. State Department spokesperson Jen Psaki discussed the move.

Jen Psaki: “So, really, this is an implementation of what we’ve been working on for months, which is cracking down on those who are violating human rights and, you know, abusers and those who are cracking down on civil society. And we announced also a couple of individuals who will be named in the first tranche of this today.”

Venezuelan President Nicolás Maduro denounced the sanctions as a further bid to undermine his government. Maduro has ordered the United States to slash embassy staff, and barred entry to Venezuela to former President George W. Bush, Vice President Dick Cheney and several members of Congress, including New Jersey Sen. Bob Menendez, who is now said to be facing corruption charges of his own. Menendez reportedly lobbied federal Medicare officials on behalf of a wealthy doctor, Salomon Melgen, who provided him with gifts and luxury vacations.

In Wisconsin, high school and college students packed the State Capitol Monday in the fourth day of protest over the killing of unarmed black teenager Tony Robinson. Police say Robinson was shot and killed in an apartment after Officer Matt Kenny responded to a report of a man jumping in and out of traffic after assaulting someone. Some 1,500 students filled the Capitol rotunda, hanging a banner that read “Black Lives Matter.”

Wisconsin Gov. Scott Walker meanwhile has signed a so-called right-to-work bill, striking a blow to organized labor four years after he gutted collective bargaining rights for public sector workers. Labor groups had staged mass protests against the bill, which makes Wisconsin the 25th “right-to-work” state. The bill Walker signed was taken practically verbatim from model legislation proposed by the right-wing American Legislative Exchange Council. It bars the mandatory collection of union dues, but critics say it is a wholesale attack on collective bargaining power.

The Missouri Supreme Court has appointed a state judge to oversee municipal court cases in Ferguson after a Justice Department report uncovered systematic racial bias and violation of constitutional rights. The Justice Department said the municipal court “primarily uses its judicial authority as the means to compel the payment of fines and fees that advance the city’s financial interest.” Ronald Brockmeyer, the municipal court judge singled out in the report for his pattern of jailing people unable to pay fines while fixing traffic tickets for himself, resigned his post. The Guardian reports Brockmeyer, who will keep his job as a prosecutor and as a judge in another town, owes $170,000 in unpaid taxes.

The University of Oklahoma has shut down a fraternity after video showed members on a bus singing a racist song. The song’s lyrics include a racial slur and a vow no black people will ever join the fraternity ”SAE.”

SAE fraternity members: “There will never be a n*gg*r in SAE.
There will never be a n*gg*r in SAE.
You can hang him from a tree, but he’ll never sign with me.
There will never be a n*gg*r in SAE.”

Hundreds of people have rallied to denounce racism on campus. University of Oklahoma President David Boren said any students identified in the video could be suspended or expelled.

David Boren: “This is not our way. These are not our values. This is not who we are. And we won’t tolerate it, not for one minute, from anybody. So, those students will be out of that house by midnight tomorrow night. The house will be closed. And as far as I’m concerned, it won’t be back, at least not while I’m president of the university.”

The Supreme Court has rejected an appeal from a Syrian man who sued the U.S. government over his seven-year wrongful imprisonment at Guantánamo. Abdul Rahim Abdul Razak al Janko was detained by the United States in 2002 after being tortured by al-Qaeda and imprisoned by the Taliban on suspicion of being a Western spy. In the lawsuit, al Janko described his time at Guantanamo as a “Kafkaesque nightmare,” saying he was tortured, beaten, subjected to sleep deprivation and urinated on by U.S. soldiers. He said he attempted suicide 17 times. In 2009, a judge ordered his release, saying the claim he was part of al-Qaeda “defies common sense.” But on Monday, the Supreme Court left in place a lower court ruling Janko cannot sue because he is an enemy combatant. Meanwhile, in a second decision, the court declined to take a case concerning videos and photographs which, according to the Center for Constitutional Rights, would prove the torture of another Guantánamo prisoner, Mohammed al-Qahtani. The move leaves in place a lower court ruling the images could threaten national security by stoking anti-U.S. sentiment.

A new report finds U.S. weapons manufacturers continue to dominate the global arms trade, with Saudi Arabia replacing India as their top market. According to IHS, the United States accounted for a third of the more than $64 billion trade in military equipment last year. This year Saudi Arabia will account for an estimated one of every seven dollars spent on military imports.

As Apple unveiled its new Apple Watch to great fanfare, a report by The Intercept finds CIA researchers have been working for nearly a decade to crack the security of Apple’s iPhones and iPads. Documents from Edward Snowden show the researchers claim to have created a modified version of Apple’s software development tool Xcode, allowing them to sneak surveillance backdoors into apps and programs.

Presumed Democratic presidential candidate Hillary Clinton will reportedly hold a news conference this week to address her exclusive use of a private email address as secretary of state. Clinton relied exclusively on a personal email account linked to a private server at her home, a possible violation of State Department rules and federal law. Meanwhile, White House Press Secretary Josh Earnest confirmed President Obama had corresponded with Clinton on her private account.

Josh Earnest: “Yes, the president was aware of her email address. He traded emails with her. That shouldn’t be a surprise that the president of the United States is going to trade emails with the secretary of state. But the president was not aware of the fact that this was a personal email server and that this was the email address that she was using exclusively for all her business.”

A United Nations report has found rampant torture by security forces in Mexico, from local and federal police, to the military. U.N. special rapporteur on torture Juan Méndez highlighted the impact of the U.S.-backed war on drugs, noting the bulk of torture cases involve prisoners with alleged ties to organized crime. Despite some 2,100 complaints of torture in 2012 alone, Mexico has seen only five torture convictions between 2005 and 2013.

Officials in Florida have reportedly banned the terms “climate change” and “global warming,” despite the disproportionate impacts of climate change in the coastal state. According to the Florida Center for Investigative Reporting, under the tenure of Republican Gov. Rick Scott, officials at the Department of Environmental Protection have been ordered not to refer to climate change or global warming in official reports or communications. ThinkProgress notes at least two other states, North Carolina and Pennsylvania, have been accused of similar bans.