There are plenty of ISIS members from the US. There were plenty of American Al Qaeeda/Taliban (remember the American Taliban?) members too. And 9/11 happened in the US. By foreign students and residents in the USA. The Pakistani couple in San Bernardino and the Muslim Major who killed multiple people were American citizens.

Canada probably has more Muslims proportionately. And while the ISIS membership of Canadian Muslims is high, no real attacks have taken place here.