Iraq's premier wants Washington's assistance against the Islamic State group, but American remarks about anti-jihadist efforts and Iran-allied organizations' strong opposition to U.S. combat troops put him in a bind.

Trying to navigate the political minefield, Haider al-Abadi has issued increasingly strident statements about foreign forces over the past week, most recently saying the deployment of such "ground combat forces (is) a hostile act."

The Islamic State group has built a base in Libya from which to exploit tribal conflicts and expand across Africa, though experts say the jihadists remain vulnerable even if the West's attention is elsewhere.

Libya's collapse into a chaotic mess of competing militias since the overthrow and death of dictator Moammar Gadhafi has made it an ideal stomping ground for IS.

There will be plenty of prayers in the wake of the latest mass shooting in the United States, but little concrete action on gun control is expected from lawmakers, despite pressure from Americans weary of the violence.

Fourteen people were killed and 21 others injured in Wednesday's shooting rampage at a social services center in San Bernardino, California that ended with the two suspects, a married couple, dead in a wild firefight with police.

Britain will bring extra precision firepower to the Syria air campaign but its participation will be no game-changer, according to experts who questioned the effectiveness of coalition air strikes in the war-torn country.

Following the green light from lawmakers Wednesday for strikes on Syria, a total of 16 Royal Air Force warplanes will be available to bomb Islamic State (IS) group targets in Syria.

An electrifying speech on Syria air strikes by the foreign affairs spokesman of Britain's Labor party brought together rival MPs in an emotional display but shone a spotlight on the opposition's deep divisions.

The House of Commons fell silent as Hilary Benn implored MPs to approve the government's plan for air strikes on Islamic State jihadists in Syria, to which his party leader Jeremy Corbyn is opposed.

Here is a breakdown of the main forces fighting Islamic State jihadists in Iraq and Syria, after British lawmakers on Wednesday voted to join the U.S.-led bombing campaign in Syria:

- Syrian and Iraqi armies -- SYRIA: The Syrian army numbered 178,000 troops in 2015, according to the International Institute for Strategic Studies (IISS). Syria's army has been roughly halved from its pre-war strength by deaths, defections and increased draft dodging. In its fight against rebels and jihadists, it relies on militias, which claim 150,000 to 200,000 members.

Riding on horseback and motorbikes, commander Naeem's fighters combed a fog-enveloped Taliban infiltration route in Afghanistan's northern badlands, as the government expands anti-insurgent militias across a patchwork of fiefdoms.

Desperate to muzzle the resurgent Taliban, the government is cultivating thousands of militias with chequered pasts as a short-term security fix to supplement ground troops suffering record casualties.

The U.S.-led coalition has made Iraqi and Syrian Kurdish forces primary allies against the Islamic State jihadist group, but over-reliance on the Kurds carries risks, analysts warn.

As the world seeks to turn up the heat on IS, some of the West's main partners on the ground are the peshmerga forces from Iraq's autonomous Kurdish region and the Kurdish People's Protection Units (YPG) in Syria.

Global oil producers, who provide the world with much of the fossil fuel that causes global warming, are in no hurry to brighten up their own image as climate dinosaurs.

Some Gulf countries have timidly started investing in renewable energy, but experts say the initiatives are just a tiny crack in producers' otherwise solid front of indifference to climate change.

Turkey's downing of a Russian jet has played into the hands of Syrian President Bashar Assad by bringing Moscow on board with his bitter opposition to Ankara, experts say.

On Thursday, Moscow announced it was preparing economic measures against Ankara two days after Turkish forces shot down a Russian plane that crashed in Syrian territory.