In an interview with ABC channel, Obama was asked about the threat by the Islamic State in Iraq and the Levant (ISIL), as his former ambassador to Iraq Ryan Crocker had described the splinter group of al Qaeda as one that " will be coming our way" with 2,000 fighters holding Western passports.
He said: "I think we have been under serious threat my entire presidency. " "And we have been under serious threat predating 9/ 11 from those who embrace this ideology."
Obama acknowledged that the group was gaining strength as it obtained more weaponry and cash in its rapid push in northern and western Iraq in the past two weeks.
"They're gaining strength in some places, but we've also got a lot better at protecting ourselves."
The Obama administration is sending as many as 300 military advisors to Iraq in addition to stepped-up surveillance and intelligence gathering in the Arab country, but it has held off air strikes on ISIL targets as requested by Iraqi Prime Minister Nuri al-Maliki.
The administration asked Congress on Thursday for 500 million dollars to train and equip vetted members of Syria's opposition, as ISIL fighters are fighting both inside Iraq and Syria.