HOUSE VOTES ON NEGOTIATIONS: The House voted by voice Tuesday evening to begin conference negotiations and name conferees for the Pentagon’s annual appropriations bill. “With the appointment of these conferees, the House and the Senate may begin to resolve the differences with the goal of passing H.R. 6157 before the end of the fiscal year,” said Rep. Tom Cole, a member of the House Appropriations Committee.

HAPPENING TODAY — THORNBERRY AWARDED: This evening at 5, Rep. Mac Thornberry, the House Armed Services chairman, will provide a keynote speech on national security and accept the Sam Nunn National Security Leadership Prize at the Center for Strategic and International Studies.

TOP LEADERS SPEAK: A slate of Pentagon officials and House lawmakers will be speaking today at a Defense News conference in Pentagon City. Adm. John Richardson, the chief of naval operations, will open the event with a keynote address at 8:30 a.m. Air Force Secretary Heather Wilson speaks at 10:15 and Defense Undersecretary for Acquisition and Sustainment Ellen Lord is scheduled for 2:30 p.m. Rep. Adam Smith, the ranking member of the House Armed Services Committee, has a fireside chat at 9:45 a.m. More information here.

PENTAGON BACKS WARNING ON CHEMICAL ATTACK: Any chemical weapons used by the Assad regime in Syria is unacceptable and will be met with a swift response, Pentagon spokesman Eric Pahon said Tuesday. “As multiple senior U.S. officials have stated, in solidarity with our allies, including Turkey, we will not tolerate the regime using chemical weapons. We will hold Assad accountable for chemical weapons use,” Pahon said in an email.

“We have engaged the Russian government and military at the most senior level to make clear that the U.S. and its partners would respond to any verified chemical weapon use in Idlib or elsewhere in Syria in a swift and appropriate manner. We encourage Russia to make this point clear to Damascus,” he said.

The statement came just hours after the White House issued its own warning statement as Syria, back by Russia and Iran, appeared to begin an assault on the country’s Idlib province. “Let us be clear, it remains our firm stance that if President Bashar al-Assad chooses to again use chemical weapons, the United States and its Allies will respond swiftly and appropriately,” Press Secretary Sarah Sanders said in the release.

SECURITY COUNCIL TO MEET ON SYRIA: The United Nations Security Council is expected to hold a meeting today to also warn Syria against the use of chemical weapons, U.S. Ambassador to the U.N. Nikki Haley told Reuters. “This is a tragic situation, and if they want to continue to go the route of taking over Syria, they can do that,” Haley said. “But they cannot do it with chemical weapons. They can’t do it assaulting their people and we’re not going to fall for it.”

Trump and the White House said the offensive in Idlib could risk the lives of hundreds of thousands of people. The Pentagon is also “gravely concerned” over the possible toll on civilians and civilian infrastructure, Pahon said. “The offensive will result in devastating humanitarian consequences,” he said.

AFGHANISTAN DEATH: A second U.S. service member died in Afghanistan on Monday, Operation Resolute Support announced on Tuesday, although this one was the result of a non-combat incident. The NATO-led operation announced on Monday that a U.S. service member had died as the result of an insider attack. That soldier was identified Tuesday night as Command Sgt. Maj. Timothy Bolyard, 42, with 3rd Squadron, 1st Security Force Assistance Brigade.

CRITICISM OVER BORDER FORCE: The decision by Defense Secretary Jim Mattis to extend the National Guard presence at the Mexico border has drawn fire as a waste of time and money from House Armed Services Committee member Rep. Anthony Brown, a retired Army Reserve colonel and outspoken critic of the border force.

“If there is a need for a National Guard deployment to the southern border, then the onus is on the executive branch to explain the costs and benefits of a deployment. As far as the American people can tell, however, this estimated $182 million use of the National Guard is solely for the purpose of placating the president’s base,” Brown said in a statement to the Washington Examiner.

WOODWARD’S EXPLOSIVE NEW BOOK: The first details of Bob Woodward’s new book “Fear” about the Trump administration were published by the Washington Post Tuesday and they include some eyebrow-raising claims about Mattis and his dealings with Trump. Here are some of the details in the Post story, apparently provided by sources on deep background:

• • Kill Assad: Trump called Mattis after a Syrian chemical weapons attack in April 2017 and said he wanted to assassinate Assad. “Let’s fucking kill him! Let’s go in. Let’s kill the fucking lot of them,” Trump reportedly said. Mattis got off the phone call and told an aide, “We’re not going to do any of that. We’re going to be much more measured.”
  • McCain’s record: During a meeting with Mattis and Joint Chiefs Chairman Gen. Joe Dunford, Trump falsely claimed the late McCain was a coward for accepting an early release from a Vietnamese prisoner-of-war camp. “No, Mr. President, I think you’ve got it reversed,” Mattis reportedly said.
  • Working with Trump: Top advisers had a low opinion of Trump. “Secretaries of defense don’t always get to choose the president they work for,” Mattis reportedly said while describing how the president goes off on tangents during conversations.
  • North Korea strike: Trump asked Dunford for a plan to preemptively strike North Korea just one month into his presidency. The move reportedly rattled the Marine general. The president told another adviser that “this is all about leader versus leader. Man versus man. Me versus Kim.”
  • Korea presence: During a National Security Council meeting, Trump wondered why the U.S. was spending any resources to have troops in South Korea. “We’re doing this in order to prevent World War III,” Mattis told him. After the president left the meeting, Mattis was “particularly exasperated and alarmed, telling close associates that the president acted like — and had the understanding of — ‘a fifth- or sixth-grader.’ ”
  • Afghanistan impatience: Trump berated generals and other national security advisers in July 2017 over Afghanistan. “The soldiers on the ground could run things much better than you,” Trump said. “They could do a much better job. I don’t know what the hell we’re doing.” The president also asked them, “How many more deaths? How many more lost limbs? How much longer are we going to be there?”
  • Sunday shows: The AP’s Zeke Miller tweeted that former White House press secretary Sean Spicer lobbied Mattis heavily to appear on the Sunday talk shows. Mattis reportedly replied: “Sean, I’ve killed people for a living. If you call me again, I’m going to fucking send you to Afghanistan. Are we clear?”

MATTIS CALLS IT ‘FICTION’: The book’s claims prompted a quick series of denials from Mattis and other administration officials, including White House Chief of Staff John Kelly, who reportedly called Trump an idiot. “The contemptuous words about the president attributed to me in Woodward’s book were never uttered by me or in my presence. While I generally enjoy reading fiction, this is a uniquely Washington brand of literature, and his anonymous sources do not lend credibility,” Mattis said in his statement, which was tweeted out by Trump.

“In serving in this administration, the idea that I would show contempt for the elected commander-in-chief, President Trump, or tolerate disrespect to the office of the president from within our Department of Defense, is a product of someone’s rich imagination.”

MORON MOMENT: The flap over what Mattis did or didn’t say about Trump represents the defense secretary’s “moron moment,” Politico reported, similar to when news surfaced that former Secretary of State Rex Tillerson had called Trump a “moron.” Mattis so far has done a good job of keeping his opinions of Trump out of the public sphere, but the Woodward book could change all of that.

“This is going to drive Trump nuts,” historian Mark Perry told Politico. “He’s going to exact his revenge.”

HALEY: NO ASSAD ASSASSINATION TALK: Haley, for her part, denied Trump wanted to assassinate Assad as reported by Woodward. “I have the pleasure of being privy to those conversations — when we’ve dealt with the chemical weapons, when we’ve dealt with the responses, when we’ve dealt with everything — and I have not once ever heard the president talk about assassinating Assad,” Haley told reporters

“So, if there are people who say certain things in the book, I’ll just tell you to take it with a grain of salt just like we’ve done every book before,” Haley said.

FEELING LONELY ON DEFENSE PACTS: Trump said Tuesday that he feels alone in his view that the U.S. should be reimbursed for the cost of protecting other countries.

“We’re protecting immensely wealthy countries and they’re not paying us for the protections,” Trump told the Daily Caller. “I say why are we protecting you when you’re very wealthy and you wouldn’t be here for two weeks if it wasn’t for us? Why aren’t we being reimbursed for this massive cost? Fully reimbursed — for this massive cost that we’re taking care of.

“Amazingly, a lot of generals don’t understand it. A lot of people don’t understand it,” Trump said, adding that he felt “amazingly alone.”

COST OF SPACE SENSORS: Michael Griffin, the undersecretary of defense for research and engineering, doesn’t believe current estimates about the cost of putting a constellation of satellites into space to detect enemy missile launches. A Center for Strategic and International Studies analysis put it at $67-$109 billion. But Griffin said Tuesday the Pentagon could do it for $20 billion.

“I get tired of hearing it would cost $100 or more billion dollars to put up a space-based interceptor layer,” Griffin said during a forum on Capitol Hill. He estimated 1,000 space-based interceptors that each weigh a metric ton would cost $20,000 per kilogram to deliver them to low orbit. Griffin said that “entirely reasonable” figure comes out to $20 billion. “We’ve paid a lot more and gotten a lot less in the Defense Department over the years,” he said.

TRUMP, MOON SPEAK AHEAD OF MEETING: Trump spoke with South Korean President Moon Jae-in Tuesday morning as Moon prepared to dispatch a special envoy to Pyongyang to resume nuclear negotiations with North Korea’s Kim Jong Un.

“The two leaders discussed the latest developments on the Korean peninsula, including our ongoing efforts to achieve the final, fully verified denuclearization of North Korea as agreed to by Chairman Kim Jong Un,” the White House said in a readout of the call.

RUSSIA ON IRAN DEAL EXIT: United Nations Security Council diplomats should review Trump’s withdrawal from the Iran nuclear deal at a coming high-level meeting in New York, according to a senior Russian diplomat.

“We hope very much aspects linked with the United States’ withdrawal from the JCPOA will be tackled,” deputy ambassador Dmitry Polyansky said, according to state-run media, referring to the Joint Comprehensive Plan of Action.

THE RUNDOWN

Washington Examiner: Trump to host special session at UN General Assembly this month

Foreign Policy: Shadowy U.S. Drone War in Africa Set to Expand

Defense News: US, Greece look at increasing military presence amid tension with Turkey

Associated Press: US’s Pompeo arrives in Pakistan hoping to ‘reset’ relations

AFP: Syrians put out fires after Russian airstrikes near Idlib

Associated Press: Death of Afghan group’s founder unlikely to weaken militants

Defense One: The China Hype

Marine Corps Times: Marines want electroshock rounds to fire from standard weapons

Roll Call: Duncan Hunter Trial Pushed Until After Election Day