UNITED NATIONS: US President Barack Obama told a gathering of world leaders on Wednesday that the terrorists only understood the language of force and that’s why he would work with the rest of the world to “dismantle this network of death”.

The US leader appeared before the UN General Assembly a day after ordering air strikes on the headquarters and bases of Al Qaeda affiliated terrorist groups in Syria, killing dozens of militants.

Know more: US led strikes kill 30 Al Qaeda fighters in Syria

“The brutality of terrorists in Syria and Iraq forces us to look into the heart of darkness … the only language understood by killers like this is the language of force,” Mr Obama told the 69th assembly of world leaders at the UN headquarters.

“So the United States of America will work with a broad coalition to dismantle this network of death.”

President Obama walked into the General Assembly hall to a polite applause. The leaders did not applaud during the speech. When he addressed the issue of Ukraine, Russian Foreign Minister Sergei Lavrov kept his head down while reading a piece of paper. Later in the speech, he flipped through a small booklet and then briefly texted on his smartphone.

Iranian representatives also showed no reaction.

Representatives of the Syrian government, which opposes the US-led military offensive because Washington rejected its offer to coordinate the attack with its force, also watched quietly, as Mr Obama spoke.

The 40-minute speech was broadcast live from the hall.

Mr Obama said that the “cancer of violent extremism” in the Muslim world could derail the progress the world had experienced since the World War II.

Urging the international community to meet this challenge, the US leader told them that they must first deal with the terrorist ground known as the Islamic State of Iraq and al Sham (ISIS), which must be degraded, and ultimately destroyed.

The group, he said, had terrorised both Iraq and Syria, using rape as a weapon to subdue civilians, beheading journalists and killing children.

“No God condones this terror. No grievance justifies these actions. There can be no reasoning — no negotiation — with this brand of evil,” Mr Obama declared.

“In this effort, we do not act alone. Nor do we intend to send US troops to occupy foreign lands,” said the president, adding that 40 nations, including Arab and Muslim states, were supporting the US-led fight against the militants.

Mr Obama warned those who have joined ISIL to “leave the battlefield while they can. Those who continue to fight for a hateful cause will find they are increasingly alone. For we will not succumb to threats; and we will demonstrate that the future belongs to those who build — not those who destroy.’’

The president said he also had a “simple” message for the countries of the Arab and Muslim world: They “must focus on the extraordinary potential of their people — especially the youth”.

Speaking directly to young people across the Muslim world, Mr Obama said: “You come from a great tradition that stands for education, not ignorance; innovation, not destruction; the dignity of life, not murder. Those who call you away from this path are betraying this tradition, not defending it.”

Mr Obama said that he would lift the sanctions imposed on Russia in case it chooses a peaceful course in Ukraine.

“A different path is available. It is the path of diplomacy and peace. The recent ceasefire agreement in Ukraine offers this path,” he said.

Published in Dawn, September 25th, 2014