Asserting that America will not succumb to threats, Obama told a gathering of world leaders at the UN General Assembly that the US would be a "respectful and constructive partner" in confronting the Islamic State militants through force.
His remarks came in the backdrop of the US and coalition partner nations launching airstrikes against the Islamic State targets, also known as ISIS or ISIL, in Syria.
He said ISIL has "terrorised all who they come across in Iraq and Syria", referring to the recent brutal beheading of two American journalists and a Briton by the terror group which had captured a large swathe of land in Iraq and Syria and declared an Islamic Caliphate.
"No God condones this terror. No grievance justifies these actions. There can be no reasoning - no negotiation - with this brand of evil. The only language understood by killers like this is the language of force. So the United States of America will work with a broad coalition to dismantle this network of death," he said.
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Calling on the world leaders "to join in this effort", Obama said America will not act alone and does not intend to send US troops to occupy foreign lands.
"Instead, we will support Iraqis and Syrians fighting to reclaim their communities. We will use our military might in a campaign of air strikes to roll back ISIL. We will train and equip forces fighting against these terrorists on the ground. We will work to cut off their financing, and to stop the flow of fighters into and out of the region," he said.
"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," Obama added.