Before the start of business, Just Security provides a curated summary of up-to-the-minute developments at home and abroad. Here’s today’s news.

SAN BERNARDINO SHOOTING

The couple responsible for the San Bernardino attack last week were both radicalized “for quite some time” and had engaged in firearms target practice ahead of the attack, the FBI said yesterday. It is as yet unclear what role Pakistani citizen, Tashfeen Malik played in the radicalization of her husband, Syed Farook. US-born Farook traveled to Saudi Arabia for an extensive vacation in 2013. [The Guardian’s Alan Yuhas; New York Times’ Adam Nagourney et al]

The Department of Homeland Security will alter the terrorism alert system so that officials use “a new system that has an intermediate level” of warning, designed to plug intelligence gaps exposed in the wake of the Paris and San Bernardino attacks. [Wall Street Journal’s Damian Paletta]

Republican presidential candidate Donald Trump has called for a ban on Muslims entering the US in the wake of last week’s attack in San Bernardino. The controversial comments have drawn criticizm from all sides, many declaring it unconstitutional. [Reuters’ Steve Holland and Emily Stephenson; New York Times’ Patrick Healy and Michael Barbaro]

In the wake of the Paris and San Bernardino attacks, White House officials are “quietly re-examining how to intensify the campaign against an elusive foe” in the Islamic State, even as the president sought to reassure the American people in his address on Sunday. [Washington Post’s Juliet Eilperin and Stevin Mufson]

President Obama’s Sunday address was “largely a plea for patience and for national unity” against the mounting terror threat, reports David E. Sanger. [New York Times]

Obama administration officials have been “conspicuously available to talk about the terror threat” and the attack in California, reports Josh Gerstein. [Politico]

“History is made, not delivered as a birthright, and victory against killers has to be won,” opines the Wall Street Journal editorial board, restating its view that President Obama does not seem to “know what it takes” for the US to defeat the ISIS threat.

It is time to start making Saudi Arabia “pay for its ideological support of extremism,” writes Charles Kenny, observing the link between the attackers and the kingdom, and discussing the various ways in which Saudi Arabia “underwrites” international terrorism. [Politico Magazine]

IRAQ and SYRIA

The US has denied that its coalition against ISIS carried out airstrikes targeting a Syrian government army camp, a military official saying that the US is certain that Russia was responsible. [Reuters’ John Davison]  Blaming the coalition, Syria’s Foreign Ministry on Monday called on the UN Security Council to take immediate action to stop further attacks. [Wall Street Journal’s Dana Ballout]

Syria’s disparate opposition will begin talks today in Riyadh, Saudi Arabia, an attempt to unify ahead of possible peace talks with other parties to the conflict. [BBC]  Some 150 representatives of political and armed groups are expected to produce a document laying out a shared vision for the country and establish a 25-member committee to represent their interests. [The Guardian’s Ian Black]

Kurdish forces will not participate in the talks, and are instead holding their own meeting in Syria’s northeastern province of Hasakah. [Al Jazeera]

At least 26 Syrian civilians have been killed by airstrikes thought to have been carried out by the US-led coalition against ISIS. According to the Syrian Observatory for Human Rights, the strikes yesterday on the north-eastern village of Al-Khan only killed civilians. [The Guardian]

US-led airstrikes continue. The US and coalition military forces carried out nine strikes on Islamic State targets in Syria on Dec. 6. Separately, partner forces conducted a further 11 strikes on targets in Iraq. [Central Command]

An Al Jazeera cameraman has died from injuries sustained during Syrian government airstrikes in Homs province last week.

Pentagon officials and government terrorism advisers have cautioned that a “reckless” escalation in the fight against ISIS could assist the militant group in recruiting disaffected Muslims around the world, reports Bryan Bender. [Politico]

Silicon Valley’s efforts to prevent terrorists from using social media “have been toothless,” according to lawmakers and even some technologists, report Nicole Perlroth and Mike Isaac. [New York Times]

The ISIS ideology is based on “prophetic texts stating that Islam will be victorious after an apocalyptic battle,” that would be prompted by Western armies sending ground troops. Rukmini Callimachi comments that these prophecies have influenced US policy, and notes Obama’s assertions to this effect during his Sunday address. [New York Times]

Recent ISIS attacks demonstrate the group’s ability to “both inspire and coordinate” terrorist attacks; Karen Yourish et al provide a visual guide to ISIS attacks in 2015. [New York Times]

“It is worth exploring the role women play in terrorism.” Mia Bloom and Charlie Winter discuss the topic, observing that “public discourse remains fixated on the irregularity of women’s motivations, expressing the belief that their participation in violent extremist groups is an unusual phenomenon.” [Politico]

YEMEN

Yemen’s President Abd-Rabbu Mansour Hadi has asked the Saudi-led coalition to start a week-long humanitarian ceasefire on Dec. 15, to coincide with UN-brokered peace negotiations. [Reuters]

Peace talks are set to take place next week in Switzerland; the talks come following months of back-and-forth by the UN envoy, Ismail Ould Cheikh Ahmed in an attempt to broker an end to the nine-month old conflict. [New York Times’ Nick Cumming-Bruce]

OTHER DEVELOPMENTS

The US will not put Ukraine in jeopardy in favor of pursuing Russian cooperation in Syria, Vice President Joe Biden told Ukrainian leaders yesterday. [New York Times’ Peter Baker]

An Air France plane on route from San Francisco to Paris was diverted to Montreal today following an “anonymous threat” made against it, according to the Air France Twitter account. [Reuters]

There is “no credible” threat of an attack by ISIS militants in Thailand, the country’s Interpol director said today following a Russian warning that 10 Syrians with ISIS links had entered Thailand. [Reuters]

The Pentagon has confirmed the deaths of senior terrorist leaders in Libya and Somalia in recent American strikes, including senior Libyan ISIS leader, Wissam Najm Abd Zayd al Zubaydi. [DoD News]

An American citizen who fought for al-Shabaab in Somalia has surrendered to the authorities, a local official said yesterday. [Reuters]

Iran breached two UN Security Council resolutions by testing a new medium-range ballistic missile on Nov. 21, two US officials said yesterday. [Reuters]

The House Homeland Security Committee is making a last minute effort to alter the language of a compromised version of a major cybersecurity bill prepared by the House and Senate Intelligence committees. [The Hill’s Cory Bennett]

The Obama administration has expressed concern that a failure by Congress to pass a year-end government spending bill would harm national security. [The Hill’s Jordan Fabian]

The majority of special operations forces oppose opening their jobs to women, according to a study on integration. Defense Secretary Ash Carter last week announced that all combat jobs will be open to women. [The Hill’s Rebecca Kheel]

The UN has made its biggest ever humanitarian appeal, calling for commitments of $20.1 billion for 2016. [UN News Centre]

The presidential campaign rhetoric in the US is harming the important US resettlement program for Syrian and other refugees, the UN refugee agency said yesterday. [Reuters]

Sens Bob Corker and Ben Cardin met with members of the UN Security Council yesterday to discuss a range of national security issues, including the fight against ISIS, the Iran nuclear accord and the humanitarian situation in Syria. [The Hill’s Jordain Carney]

Expanded Internet access has brought some serious challenges, “like threats to free speech, qualms about surveillance and fears of online terrorist activity.” Eric E. Schmidt writes about how to build a “better web,” at the New York Times.

An unreleased congressional report on the Bowe Bergdahl swap presents a new angle on the trading of Bergdahl for five Taliban fighters. Shane Harris and Nancy A. Youssef provide the details. [The Daily Beast]

An Iraqi man with extremist connections has been arrested in Italy on suspicion of helping foreigners travel illegally through the southeastern port city of Bari. [New York Times’ Elisabetta Povoledo]