WASHINGTON – Top Trump administration officials told lawmakers Tuesday that U.S. military deployments in the Middle East were purely defensive and not aimed at provoking a war with Iran, amid growing concerns in Congress about a possible military conflict.

Secretary of State Mike Pompeo and Acting Defense Secretary Patrick Shanahan briefed members of the House and Senate behind closed doors, detailing what they called "credible intelligence" that suggests a possible Iranian attack on American military forces in the region.

Shanahan said the Trump administration's decision to deploy B-52 bombers and other military resources to the Persian Gulf had succeeded in preventing a possible strike on U.S. interests.

"We have deterred attacks based on our posturing of assets – deterred attacks against American forces," he told reporters after the congressional briefings.

"Our biggest focus at this point is to prevent Iranian miscalculation," Shanahan added. "We do not want the situation to escalate. This is about deterrence, not about war."

But lawmakers were divided, mostly along partisan lines, about the nature of the threat from Iran and whether the Trump administration's response was making the situation better or worse.

Some Democrats raised alarms Tuesday that the Trump administration was cherry-picking intelligence information to justify a military conflict with Iran.

“We’re concerned that information is being used for the purposes of accomplishing an objective, rather than for the purposes of making a decision,” House Majority Leader Steny Hoyer, D-Md., told USA TODAY after he and other House Democrats met privately with former CIA Director John Brennan and former Ambassador Wendy Sherman, both of whom served in Obama administration.

“Let’s hope that the administration is not rationalizing a move towards war,” Hoyer added.

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Rep. Adam Schiff, D-Calif., chairman of the House Intelligence Committee, said the president and his advisers are sending mixed messages on the seriousness of the threat from Iran. He noted that while Pompeo and others have talked about "credible" intelligence about an Iranian attack on U.S. military personnel, President Donald Trump suggested on Monday there was no imminent threat.

"We have no indication that anything’s happened or will happen, but if it does, it will be met, obviously with great force,” Trump told reporters as he left the White House for a campaign rally in Pennsylvania Monday evening.

“It’s hard to know what the administration is portraying at this point,” Schiff told reporters after the meeting with Brennan and Sherman. He said he’s deeply worried that the administration’s lack of “any clear thought, plan (or) strategy has just multiplied the risks” of conflict.

Rep. Elissa Slotkin, a Michigan Democrat and former CIA analyst who studied Iranian proxy groups, said the Trump administration's incoherent strategy risked the possibility of an inadvertent conflict.

“The president vacillates between saying that he cares only about the nuclear file and increasingly threatening on Twitter to essentially wipe Iran off the map,” Slotkin said. “If I and you cannot understand U.S. strategy, then you can bet the Iranians don’t understand it. And if neither side can determine what actions are offensive versus defensive, it sets us on a course to misunderstanding each other and a slide towards war.”

Trump vowed to "end" Iran Monday after a Katyusha rocket landed in Baghdad's heavily fortified Green Zone less than a mile from the U.S. Embassy. The rocket did not cause any injures; officials believe it was fired from east Baghdad, an area controlled by Iran-backed Shiite militias.

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Skoltin said Iran has been a malign actor in the region for decades and any recent intelligence needed to be taken into that broader context.

"I spent some years in Baghdad during much more volatile times, when 40 or 50 rockets a day we’re coming into the green zone," she said. "It has to be looked at in context and not just cherry picked" to suggest a new or escalating threat.

Republicans said the Trump administration's actions have been prudent and the threat from Iran was direct and worrisome.

"The intelligence was pretty clear. It was new and escalating," said Rep. Michael McCaul, the top Republican on the House Foreign Affairs Committee. "They’re the ones who fired a rocket in the green zone near our embassy," he said.

McCaul did not cite specific evidence to back that up. But he argued the Trump administration's moves were "purely defensive."

He and other Republicans dismissed suggestions that the U.S. military deployments and the sharp rhetoric from Trump and his advisers could lead to a miscalculation or miscommunication that results in war with Iran.

But Democrats said they feared just that. They note that since Trump administration withdrew from the 2015 Iran nuclear deal, there are no formal channels of communication with the regime. That Obama-era deal was aimed at curbing Iran's nuclear ambitions.

"There’s a huge risk of Iran miscalculating, striking in a way that gets a response they didn’t anticipate," said Rep. Adam Smith, D-Wash., the chairman of the House Armed Services Committee. "There’s a risk for miscalculation on both sides. That remains my biggest concern."

He said Pompeo and other officials told lawmakers there were some "back channels" to talk to the Iranians if needed. But Democrats were not reassured.

"This is blind escalation with the hope that the Iranians will come to the table in the end or the hope that the Iranians will rise up and topple the regime," said Sen. Chris Murphy, D-Conn., a member of the Senate Foreign Relations Committee.

He said the threats from Iran were a predictable response to the Trump administration's efforts to squeeze Iran with severe economic sanctions and to isolate the regime diplomatically by withdrawing from the nuclear deal and pressing other parties to that agreement to abandon it.

The Trump administration should have known the Iranians would consider attacking American assets in the region, Murphy said, arguing that was "entirely predictable given the steps we've taken."

The U.S. show of military force hasn't done anything to change Iranian behavior, he said.

"The Iranians are no closer to talking than ever before. They do not seem to be backing down from a standing point of military provocation," Murphy said.

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