Sparks flew during the first presidential debate between Republican Donald Trump and his Democratic opponent Hillary Clinton over plans to defeat the Islamic State, nuclear proliferation and threats to cybersecurity, among other national-security issues.
Trump quickly went on the offensive during the 90-minute televised debate moderated by NBC's Lester Holt on Monday night at Hofstra University in New York -- the first of three such events planned -- notably when he accused Clinton of sharing too much information by outlining a plan to defeat the terrorist group known as the Islamic State of Iraq and Syria, or ISIS.
"She's telling us how to fight ISIS," Trump said. "Just go to her website. She tells you how to fight ISIS on her website. I don't think Gen. Douglas MacArthur would like that too much."
Clinton responded, "At least I have a plan to fight ISIS."
Trump: "You're telling the enemy everything you want to do ... no wonder you've been fighting ISIS your entire adult life."
Clinton is 68 years old.
While its ideological and organizational roots date to 2002, the Islamic State of Iraq and Syria -- an offshoot of the terrorist group al-Qaida -- was formed in April 2013, according to a June report from the Congressional Research Service, a nonpartisan think tank that publishes studies on topics requested by members of Congress.
That's when a group leader and onetime U.S. detainee "Abu Bakr al Baghdadi announced his intent to merge his forces in Iraq and Syria with those of the Syria-based, al-Qaida affiliated group Jabhat al Nusra (Support Front), under the name of the Islamic State of Iraq and the Levant (ISIL/ISIS)," the document states.
On her website, under a section titled, "Combating terrorism and keeping the homeland safe," Clinton lists three bullet points as part of a strategy for defeating ISIS.
They include "intensifying the coalition air campaign against ISIS fighters, leaders, and infrastructure; stepping up support for local Arab and Kurdish forces on the ground and coalition efforts to protect civilians; and pursuing a diplomatic strategy aimed at resolving Syria's civil war and Iraq's sectarian conflict between Sunnis and Shias -- both of which have contributed to the rise of ISIS."
During the debate, Clinton acknowledged she "put forth a plan to defeat ISIS."
"I would do everything possible to take out their leadership," she said, noting her role in supporting the U.S. special operations raid that killed al-Qaida leader Osama bin Laden in 2011. "I think we need to go after Baghdadi, as well, make that one of our organizing principles."
Clinton also called for increasing U.S. and coalition airstrikes "to actually take out ISIS in Raqqa," the group's self-proclaimed capital in Syria, and "end their claim of being a caliphate."
"We're making progress," she said of the ongoing operations in Iraq, where some 5,000 American troops are serving, and in Syria, where an estimated 300 U.S. special operations forces are deployed. "Our military is assisting in Iraq and we're hoping that within the year we'll be able to push ISIS out of Iraq and then really squeeze them in Syria."
Clinton also proposed working with American technology firms "to prevent ISIS and their operatives from being able to use the Internet to radicalize, even direct, people in our country, in Europe and elsewhere."
Both Trump and Clinton said they would support a law that prevents a person from acquiring a gun if they appear on a terrorist watch list.
"Right now, we've got too many military-style weapons on the streets. In many places, our police are outgunned," she said. "If you are too dangerous to fly, you're too dangerous to buy a gun." Trump said, "I agree with you … I think we have to look very strongly at no-fly lists and watch lists."
Yet Trump, 70, criticized Clinton for her pledge to "take out ISIS."
He blamed President Barack Obama and Clinton for supporting policies that "created a vacuum the way they got out of Iraq," referring to the instability following the 2011 withdrawal of U.S. troops from the country. "They shouldn't have been in, but once they got in, the way they got out was a disaster, and ISIS was formed," he said. "She talks about taking them out -- she's been trying to take them out for a long time."
Trump said ISIS "wouldn't have even been formed" had the U.S. left 10,000 or more troops in Iraq. He also repeated his statement that the U.S. should have seized Iraqi petroleum assets, which he said became the terrorist group's "primary source of income." He didn't elaborate.
The Republican presidential candidate also reiterated that he was "against the war in Iraq," which the U.S. launched with allies in 2003. The previous year, when asked by radio host Howard Stern if he was for a U.S. war in Iraq, Trump said, "Yeah, I guess so. I wish the first time it was done correctly." On Monday, he said of the exchange it was the first time anyone had asked him the question and that he made the remarks "very lightly." He also said he repeatedly told Fox News host Sean Hannity he was against the U.S.-led operation.
Clinton said President George W. Bush, not Obama, made the agreement for when troops would leave the country.
Clinton said "cyberwarfare will be one of the biggest challenges facing the next president." While some hackers do it for commercial gain, "increasingly we are seeing cyberattacks coming from states, organs of states, the most recent and troubling of these has been Russia." She went on to blame Russia for hacking the Democratic National Committee, among other entities.
"We need to make it very clear, whether it's Russia, China, Iran or anybody else, the United States has much greater capacities and we are not going to sit idly by and permit state actors to go after our information -- our private sector information or our public sector information," she said.
Responding to Clinton's claim that 50 national-security officials said Trump was "unfit" to be commander in chief, Trump said has received the support "to lead this country" from more than 200 retired admirals and generals, in addition to many more immigration officials and border-patrol agents. "I'll take the admirals and I'll take the generals any day over the political hacks," he said. "Look at the mess that we're in."
On cybersecurity, Trump said he agreed with "parts" of Clinton's statements but questioned whether Russia was behind recent hacking of the political group.
"We should be better than anybody else and perhaps we're not," he said. "I don't think anybody knows it was Russia that broke into the DNC. She's saying Russia, Russia, Russia … Maybe it was. It could be Russia, but it could also be China. It could also be lots of other people. It could also be somebody on their bed, weighing 400 pounds."
Both Trump and Clinton agreed the risk of global nuclear proliferation is a significant threat to U.S. national security.
Clinton defended her support for the Iran nuclear deal and attacked Trump's previous comments suggesting the U.S. may benefit from such allies as Japan, South Korea and Saudi Arabia developing nuclear weapons.
"His cavalier attitude about nuclear weapons is so deeply troubling," she said. "That is the No. 1 threat we face in the world and it becomes particularly threatening if terrorists ever get their hands on nuclear material."
Clinton said NATO came to the collective defense of the U.S. in the wake of the Sept. 11, 2001, terrorist attacks in New York City and Washington, D.C. -- and that the alliance continues to assist U.S. military operations in Afghanistan, where more than 9,800 American troops and 6,300 international troops are deployed.
"A man who can be provoked by a tweet should not have his fingers anywhere near the nuclear codes," Clinton said, referring to Trump's comments during a campaign event this month that under his administration Iranian boats threatening U.S. Navy destroyers "will be shot out of the water."
Trump, who pledged to release his tax returns when Clinton released her missing emails while secretary of state, said the U.S. vastly outspends NATO allies on defense and security. Indeed, according to NATO's own report from July, only five members -- the U.S., Greece, United Kingdom, Estonia and Poland -- met the guideline for spending at least 2 percent of gross domestic product on defense.
"The single greatest problem the world has is nuclear armament and nuclear weapons -- not global warming," he said. "We defend Japan. We defend Germany. We defend South Korea, We defend Saudi Arabia. They do not pay us what they should be paying us."
"We're a country that owes $20 trillion," he added, referring to the U.S. national debt. "They have to help us out."