US President Barack Obama has defended his decision not to use the term 'Islamic terrorism', saying it is a "sort of manufactured" issue and there is no religious rationale to associate Islam with those who kill people. "The truth of the matter is, is that this is an issue that has been sort of manufactured, because there is no doubt that where we see terrorist organiasations like Al Qaida or ISIL, they have perverted and distorted and tried to claim the mantle of Islam for an excuse for basically barbarism and death," Obama said at a military town hall in Virginia. "These are people who kill children, kill Muslims, take sex slaves. There's no religious rationale that would justify in any way any of the things that they do," he said. Obama said he has been careful to make sure he does not lump these "murderers" into the billion Muslims that exist around the world, including in this country, who are peaceful, who are responsible, who in this country are troops and police officers and firefighters and teachers and neighbours and friends. "What I learned from listening to some of these Muslim families both in the United States and overseas is that when you start calling these organisations 'Islamic terrorists', the way it's heard, the way it's received by our friends and allies around the world is that somehow Islam is terroristic. "That then makes them feel as if they're under attack. In some cases, it makes it harder for us to get their cooperation in fighting terrorism," Obama said in response to a question. "If somebody uses the phrase 'Islamic terrorism' that it's a huge deal? No There's no doubt that these folks think that - and claim that they're speaking for Islam. But I don't want to validate what they do." Obama said even some people "aspiring" to be president should refrain from such language. He said religious tests for immigration were a "slippery slope." "The dangers where we get loose in this language, particularly when a president or people aspiring to become president get loose with this language, you can see in some of the language that we use - in talking about Muslim-Americans here, and the notion that somehow we'd start having religious tests in who can come in the country, and who's investigated, and whether the Bill of Rights applies to them in the same way," he said.