"We built a global coalition, with sanctions and principled diplomacy, to prevent a nuclear-armed Iran. And as we speak, Iran has rolled back its nuclear program, shipped out its uranium stockpile, and the world has avoided another war," Obama said, in his only mention of Iran in his final State of the Union speech.
Just hours earlier, he was alerted that the sailors were being held in Iran after two small U.S. naval craft entered Iranian waters, according to U.S. defense officials.
Arizona Sen. John McCain, once Obama's GOP challenger for the presidency, blasted the speech for not including any reference to the incident in the Persian Gulf.
"Ten American sailors have been taken into custody in Iran," he said in a statement. "But President Obama completely omitted this latest example of Iran's provocative behavior so as not to interfere with his delusional talking points about his dangerous nuclear deal with Iran.
House Majority Leader Kevin McCarthy also slammed the omission.
"I was very concerned that he's missing where the challenge of the world is with security -- he sits and talks positively about Iran when they just took 10 of our Navy sailors," he said after the speech.
Secretary of State John Kerry told CNN's Dana Bash that he expected the sailors to be released "very soon" but would not be more specific. He was speaking at the Capitol ahead of the start of Obama's speech.
A senior administration official said there is nothing to indicate this was a hostile act on the part of any entity in Iran, adding that the U.S. has received high-level assurances that the sailors would be released promptly.
There has been voice contact with the sailors captured in Iran, a senior U.S. official told CNN. The sailors -- nine men and one women -- said they expected to be released in the morning. The official said the plan is to meet the sailors in international waters after dawn, but did not say whether the two boats would be returned with the service members.
"Certainly, everybody should be aware of the fact we have been in touch with the Iranians and they have assured us that our sailors are safe and that they'll be allowed to continue their journey promptly," White House Press Secretary Josh Earnest told CNN's Jake Tapper.
The U.S. is uncertain whether the vessels, which were sailing near Farsi Island in the Persian Gulf, intentionally entered Iranian waters, and the senior defense official said no distress call was made by the ships.
Another senior defense official told CNN the boats were in the vicinity of Farsi Island for refueling. It's not clear whether they were refueled, raising the possibility they ran out.
The U.S. lost contact with the two ships, which were en route from Kuwait to Bahrain, a senior administration official told CNN.
Kerry started immediately reaching out to Iranian Foreign Minister Mohammad Javad Zarif once he was notified of the incident, according to a senior administration official. When Kerry reached Zarif on the phone, he explained that the boat had a mechanical problem and that the boat accidentally strayed. Zarif assured Kerry the sailors were being treated well and would be released.
But former House Intelligence Committee Chairman Mike Rogers, a Republican, criticized Kerry for attending the State of the Union before the sailors were released.
"The secretary of state should not say, 'It's gonna be soon, real soon,'" Rogers said on CNN. "We need to have the secretary of state engaged in this issue right now. In fact, I'm not sure I would have him at this speech."
Roger also dismissed the idea, put out by the administration, that the transfer of the sailors could not happen at night because it would be too dangerous.
"This notion that it happens at night and can't be done safely is absolute hooey, absolute hooey," Rogers said. "This should be done, it should be done immediately, and I think every level of our government should be applied to this, including our secretary of state."
Farsi Island is an area where the Iranian Revolutionary Guard Corps -- which the semi-official Fars News agency said detained the service members -- tends to operate, and they are much more aggressive than the Iranian Navy.
The Fars News agency also reported that the American boats were equipped with three, 50-caliber machine guns. The boats crossed a little more than a mile into Iranian-patrolled waters, reported Fars, which cited information recorded on the GPS device of the American vessels and now in the hands of the IRGC.
Iran's official state news agency, IRNA, reported that the boats were "rescued" by Iranian navy sailors.
Iranian representatives at the U.N. mission in New York had no comment.
A shadow on State of the Union Address
House Speaker Paul Ryan said in a statement that he was "closely monitoring the situation," and Republican Colorado Sen. Cory Gardner suggested to Tapper on CNN that the President delay the start of the speech.
"I think the White House needs to be honest and transparent as quickly as possible with the members of the Congress, the House and the Senate," Gardner said before the address began.
The issue quickly became a discussion topic on the 2016 campaign trail.
GOP front-runner Donald Trump, speaking at a campaign rally in Cedar Falls, Iowa, said the incident highlighted that the U.S. "isn't the same country."
"It's just an indication of where the hell we're going," Trump said. "I mean, hopefully, they get released and fast. But it seems to be an indication of where we're going."
Retired neurosurgeon Ben Carson tweeted: "While POTUS is preparing to talk about his so called "accomplishments", 10 of our American sailors are being held by #Iran."
And former Florida Gov. Jeb Bush tweeted: "If our sailors aren't coming home yet, they need to be now. No more bargaining. Obama's humiliatingly weak Iran policy is exposed again."
Texas Sen. Ted Cruz also joined in the Obama-bashing. "This is the latest manifestation of the weakness of Barack Obama, that every bad actor ... views Obama as a laughingstock," he said.
Former Pennsylvania Sen. Rick Santorum demanded the sailors' immediate return.
"WH says our sailors are being given courtesies? This is feckless. WH is endangering our troops. Demand their return NOW!" he tweeted.
Impact on nuclear deal
The arrest of the sailors came days before the deal agreed to between Iran and world powers to freeze Tehran's nuclear program is expected to go into force. The IRGC is typically seen as a hardline opponent of President Hassan Rouhani's more moderate government, which engineered the deal but has had little choice to fall in behind it after the negotiations were endorsed by Iran's Supreme Leader Ayatollah Ali Khamenei.
The IGRC, which is largely responsible for Iran's nuclear research, is also expected to benefit financially from the lifting of sanctions under the pact in return for a halting of Tehran's nuclear program. But the lifting of sanctions is what is due to begin with the pending implementation, and this incident could throw a wrench in the works.
The capture of the Navy sailors was quickly seized on by U.S. opponents of the nuclear deal as the latest in a series of provocations by Tehran since the deal was agreed, which include aggressive attempts to wield power in its immediate neighborhood and ballistic missile tests that the United Nations charged violated a Security Council resolution.
"This kind of openly hostile action is not surprising. It's exactly what I and so many others predicted when President Obama was negotiating the nuclear deal with Iran -- that it would embolden their aggression towards the United States and our allies in the region," Arkansas Republican Sen. Tom Cotton told Blitzer on "The Situation Room."
Cotton also pointed to its timing right before the State of the Union.
"It's humiliating to Barack Obama and therefore the United States to have American sailors held hostage during his final State of the Union," Cotton said.
Florida Sen. Marco Rubio, another 2016 Republican presidential candidate, also criticized Obama and the nuclear deal.
"Iran is testing the boundaries of this administrations resolve and everybody knows the boundaries are pretty wide and the administration is willing to let them get away with many things. You'll only see this accelerate since the deal was signed with Iran," he said. "That's why as president on my first day in office I will repeal the nuclear deal that Barack Obama has signed with Iran."
Earnest, however, pushed back on the criticism of the deal.
"Certainly the United States has been concerned of the kind of provocative destabilizing actions that have been a hallmark of Iranian behavior over the last several decades," Earnest said. "In fact, that is why ... the United States and this president made it a priority to organize the international community to reach an agreement with Iran that will prevent them from obtaining a nuclear weapon."
The rising tensions between Iran and other regional powers and the United States also may play into a volatile political environment inside the country ahead of crucial elections in the Islamic Republic next month for the country's parliament, the Majlis, and a powerful body called the Assembly of Experts that has the power to appoint the supreme leader.
Back in 2007, Iran captured 15 British sailors and marines in the Persian Gulf and accused them of trespassing in Iranian territorial waters before releasing them almost two weeks later. The British service members were paraded before then President Mahmoud Ahmadinejad and critics said their apologies were extracted under duress. Britain maintained that its service members never entered Iranian waters.
In 2004, three British patrol boats
were boarded and seized by Iranian security forces in the Shatt al Arab waterway which divides Iraq and Iran. The crew of the three boats, including eight British sailors and marines, were blindfolded and paraded on Iranian state television and held captive for three days.
After the 2007 seizure, then-Chief of Naval Operations Adm. Mike Mullen told CNN's Barbara Starr that, "We've got procedures in place which are very much designed to carry out the mission and protect the sailors who are there, and I would not expect any sailors to be able to be seized by the Iranian navy or the Iranian Republican Guard."