WASHINGTON -- When Sen. Chris Murphy (D-Conn.) recently gave a speech challenging the United States' long-standing indulgent relationship with Saudi Arabia, he did it in New York, where experimentation and radical thinking are more common than in stodgy D.C.

But the nation’s capital was listening closely. And some of its most influential players liked what they heard.

Murphy later told The Huffington Post that many of his fellow lawmakers have for some time been privately expressing the criticisms he made of Saudi Arabia -- namely, that it has encouraged the spread of a fundamentalist, intolerant strain of Islamic thought, and that the war it is fighting with U.S. support in Yemen has achieved little besides giving al Qaeda more room to flourish.

“For whatever reason, even Congress, without these personal relationships [with Saudi officials], hasn’t been willing to say some of the things that I’ve been saying publicly over the last week,” Murphy told the HuffPost Politics podcast "So, That Happened." But, he said, none of his colleagues in the Senate have told him anything that suggests they disagreed with his speech.

Asked if he had received any pushback from Saudi representatives in the U.S., Murphy said he had not spoken to any of them in person since the address.

“I’m sure there are those in the embassy who aren’t happy with it,” the senator said.

Go to the 31:00 mark to hear Murphy's full interview with HuffPost on the U.S.-Saudi relationship.

Murphy's remarks might seem startling, given how close the U.S. has been to the kingdom and how often the Saudis have helped achieve American goals across the Middle East. But recent shifting attitudes in Washington have made this the right moment for Murphy to announce his skepticism of the Saudis -- and he's framed his argument in a way that makes it difficult to challenge.

Two current Obama administration officials, and one who recently departed, have praised Murphy's address in separate conversations with HuffPost, each one saying they are glad an influential figure is publicly asking questions about the U.S.-Saudi bond.

Such thinking has become popular in Washington over the past few years as the administration has prioritized the goal of a nuclear agreement with Iran, Saudi Arabia’s top competitor for influence in the Middle East.

The Saudis did not publicly criticize the negotiations between the U.S., other world powers and Iran -- which is one reason the Obama administration was able to finalize and win congressional approval for a deal that experts say will strongly limit Iran’s ability to build a nuclear weapon. But Saudi figures did repeatedly point out some of the same examples of Iranian interference in the region that critics of the deal cited to argue against it. And Saudi Arabia, like the United Arab Emirates and other U.S.-friendly Arab monarchies, also suggested that President Barack Obama was paying too little attention to Iranian misbehavior in his pursuit of a deal -- implying that the diplomatic victory and security benefits would come at too high a cost.

To celebrants of the U.S.-Iran deal -- a group that includes the Obama administration and most of Washington's foreign-policy community -- that kind of argument isn’t in vogue right now.

For many officials and public figures who welcome the Iran deal, the Saudis' protestations make the kingdom look at best outdated -- unable to grasp the value of a future where diplomacy is possible with a long-vilified, historically important country -- and at worst selfish, desperate to keep U.S. support flowing to only one side of the proxy war that Saudi Arabia and Iran have been fighting for decades. The Obama administration has tried to assuage the concerns of Saudi Arabia and its other partners in the Muslim world, but it's done so primarily by providing various kinds of military support -- arms sales, backing for the Yemen campaign -- which makes the kingdom look even less friendly in a climate where all the focus is on a new peace with Iran.

So even though outside observers are also expressing concern about Iran in contexts beyond the nuclear deal, cheerleaders of the deal have tended to dismiss the issue as an unfashionable Saudi obsession. (It doesn't help that Israel, the other important U.S. foreign partner critical of the deal, has lately seen its stock fall in Washington due to Prime Minister Benjamin Netanyahu's tensions with Obama.)

Saudi Arabia's own resistance to change has only reinforced that unfavorable impression. Long known as a notorious human rights violator, the country remains harsh in a world where brutality is increasingly hard to hide. It has drawn condemnation by targeting well-known Saudi reformers like Raif Badawi and attorney Waleed Abu al-Khair, and it executed more people last year than it has in any year since 1995. Its slowness to develop sectors of its economy beyond the oil business, something it says it is now working hard on, has left many young Saudis without viable paths to a future -- at least, a future not funded by government coffers that might not always be full. In April, after the first hurdle to the Iran deal was cleared, Obama told The New York Times that the Sunni Arab monarchies should focus on the internal threat posed by frustrated youth more than the external boogeyman of Iran. That comment still rankles Gulf officials.

At the same time, the kingdom’s traditions have left it open to unfortunate charges -- most strikingly, the accusation that it resembles the self-styled Islamic State militant group. That claim has become popular on social media and in Iranian propaganda, and has even made its way into the Times. Hussein Ibish, a prominent scholar at the Saudi-backed Arab Gulf States Institute, wrote about the comparison in November, calling it “a false equation [with] troubling echoes.”

Though the kingdom does not engage in Islamic State practices like sex slavery, massacres of religious minorities or major international terror plots, “the problem for Saudi Arabia is that were one to scan the Muslim world for analogies to ISIL’s beliefs and conduct, one of the most obvious comparisons must be with the official and quasi-official interpretations of Islam that have been enacted, and, indeed, promoted by Saudi Arabia,” Ibish argued, using an alternative term for the militant group.

Now added to the list of acts to which Americans don’t want their top allies linked are the many cases of civilian casualties reportedly caused by the ongoing Saudi war in Yemen.

Iran, meanwhile, is enjoying a moment. Successfully complying with the requirements of the nuclear deal and obtaining sanctions relief in January, as well as then releasing American prisoners in return for Iranians held in the U.S., has given the Islamic Republic a chance to show that it can be a responsible world player. Its front-line role in the fight against the Islamic State has burnished that image. Though Iran's support for Syrian President Bashar Assad is a top recruiting point for the extremists, it has recently downplayed that association by reducing the visibility of its role in Syria -- allowing its partner in the pro-Assad coalition, Russian President Vladimir Putin, to take the lead in manipulating international views of the civil war there.

Amid this perfect storm for a decisive reset in U.S.-Saudi relations, sources close to the kingdom paid close attention to Murphy’s speech. But though they say it unfairly minimized the help the Saudis have given Americans in their various foreign adventures over the years, the senator’s careful phrasing made it hard for them to offer a stronger rebuttal.

Murphy was clear on the value of the U.S. partnership with Saudi Arabia. He noted that the kingdom is vital to the global battle against Islamic terror and in the conflict in Syria, where it is the major source of funding and political leadership among the various anti-Assad Syrian Arab factions that the West prefers over either the Assad regime or ISIS.

He also avoided directly equating Saudi Arabia with ISIS, pointing instead to the diffuse but definite link between Saudi-backed ideology and fundamentalism in the Muslim world. That connection cannot be blamed for all Islamic State recruitment -- Ibish notes that one of the major sources for ISIS fighters is Tunisia, the Arab country least influenced by Saudi Arabia. But that kind of ideology has helped reduce overall levels of tolerance in Muslim societies and spread the kind of thinking that might lead people to donate to or otherwise support extremists, if not actually join them.

The kingdom knows it needs to work on its image, Saudi-linked sources told HuffPost. Fahad Nazer, a former analyst at the Saudi Embassy in Washington who now works at the consulting firm JTG, pointed to Saudi efforts like op-eds by the country's foreign minister. He also cited more mysterious advocates for Saudi Arabia, like the anonymous Twitter account @ArabianVeritas, which tweets a steady stream of pro-Saudi information and often emphasizes the ways the kingdom has helped support U.S. foreign policy. (ArabianVeritas did not respond to a HuffPost inquiry about its origins.)

And Washington, which has gotten over serious frustrations with the Saudis before, is probably not going to walk away from the relationship any time soon.

Still, the days that Murphy cautioned against in his remarks -- those of the U.S. reflexively supporting any Saudi endeavor or misstep -- just may be numbered.

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