At a Senate Armed Services committee hearing, Sen. John McCain (R-Ariz.) said it was “astounding” that Energy Secretary Ernest Moniz has not seen the agreement between Iran and the International Atomic Energy Agency on inspection of the country's nuclear weapons facilities. (AP)

Gen. Martin E. Dempsey, the outgoing chairman of the Joint Chiefs of Staff, gave what one lawmaker called a “tepid” endorsement of the Iran nuclear deal Wednesday, as the Obama administration did public battle for the third time in a week with congressional Republicans opposed to the agreement.

Dempsey, who said he kept his nine-sentence opening remarks brief because he had only recently testified before the same Senate Armed Services Committee, disputed the description.

“I would ask you not to characterize my statement as tepid, nor enthusiastic, but rather pragmatic,” Dempsey told Sen. Roger F. Wicker (R-Miss.). The negotiated deal was better than launching a military strike against Iran, Dempsey said, “but I will sustain the military options in case that becomes necessary.”

Defense Secretary Ashton B. Carter provided somewhat more outspoken support of the agreement he called “a good deal” that would remove one “critical element of risk and uncertainty from the region.”

The hearing was billed as an examination of the strategic and military ramifications of the Iran agreement across the Middle East, beyond its aim of preventing Iran from developing a nuclear bomb.

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“When we consider these broader strategic consequences of the agreement — the second-order effects,” Chairman John McCain (R-Ariz.) said, “what is already a bad deal only looks that much worse.”

Congress has until late September to decide whether to vote on a resolution of “disapproval” of the agreement. Obama has said he would veto any such legislation, and the administration reiterated Thursday that it believes critics in Congress lack the two-thirds majority needed to override such a move.

Treasury Secretary Jack Lew, speaking early Thursday at a press breakfast sponsored by the Christian Science Monitor, said he was “confident that we can prevail.”

McCain opened the hearing by noting that he had invited only Carter and Dempsey to testify but that Secretary of State John F. Kerry, Energy Secretary Ernest Moniz and Lew showed up as well.

Kerry and Moniz led the negotiations with Iran and have already testified twice, with Lew, on the Iran deal.

Sen. Joni Ernst (R-Iowa) noted that President Obama had said in media reports that the “choice is the Iran nuclear deal or war.” Had Dempsey, she asked, told the president the choice was “we either take this deal or we go to war?”

“No, at no time did that come up in our conversation, nor did I make that comment,” Dempsey said. “I can tell you that we have a range of options, and I always present them.”

Obama’s actual statement when the deal was announced July 14 was that “No deal means a greater chance of more war in the Middle East.”

While some questions centered on defense concerns raised by regional allies and whether Iran would increase its sponsorship of terrorist activities in the region with funds garnered from sanctions relief, many plowed more familiar ground.

Senators again inquired about a confidential agreement between Iran and the International Atomic Energy Agency about verification of its past nuclear activity. “What Congress would like is the text of these agreements as required by law,” said Sen. Tom Cotton (R-Ark.).

Kerry said, as he has previously, that the side agreement is a “standard” part of the way the IAEA does business, and that such accords between the agency and an individual country are confidential. He said that U.S. negotiators had been briefed on its contents and would brief Congress.

Moniz, in response to prompting from Sen. Angus King (I-Maine), said that the IAEA agreement covered only Iran’s “past” behavior, and that the main agreement covers inspection and verification of Iranian compliance going forward.

Sen. Deb Fischer (R-Neb.) questioned the deal’s mechanisms for resolving allegations of cheating by Iran, and how much time might pass before inspectors can examine an undeclared site. As she read the agreement, Fischer said, “I think we have the potential that we’re looking at an 89-day delay” from when a cheating allegation is lodged until Iran is compelled to grant access to the location.

Moniz disputed that interpretation, saying there is a “24-day clock and that’s the end.”

But later in the day, Fischer’s office issued a press release, headlined: “Text of Agreement Gives Iran 89 Days, while Administration Claims 24.”

When Sen. Jeff Sessions (R-Ala.) asked Carter whether the deal allowed Iran “to purchase anything they need on the world market” after a conventional weapons ban is lifted in five years, and prohibitions on ballistic missiles technology and parts in 10 years, Kerry interjected: “No, Senator. Could I answer that? It actually does not.” Other prohibitions unrelated to the nuclear deal would remain in force to prevent such actions, Kerry said. Kerry said that later this week he will travel to the Persian Gulf “to lay out the very specifics of the proposal for how we are going to push back against Iran,” should it expand what lawmakers and witnesses alike called it’s “malign activities” in the region.

Those activities, Dempsey said in his clipped opening statements, “run the gamut from ballistic missile technology to weapons trafficking, to the use of surrogates and proxies to naval mines and undersea activity, and last but not least to malicious activity in cyberspace.”

“The negotiated deal does not alleviate our concerns in those five areas,” he said, or “change the military options at our disposal . . . we will continue to engage our partners in the region to reassure them and to address these areas.”