The shooting in Boston on Wednesday night left five people dead and more than 170 injured.
It also left President Donald Trump to claim he had ordered a “complete shutdown of Muslims entering the United States”.
The President and his administration have repeatedly blamed the attack on “radical Islamic terrorism”.
In the wake of the shooting, Trump, his wife Melania, and their son Barron were held in a hotel room in Washington.
The President also defended his call to bar all Muslims from entering the US.
“We are not a country that tolerates violence, or those who incite violence, and those who do not respect our constitution and our laws,” he said.
The US president was responding to criticism over his statement, in which he claimed to have ordered a complete shutdown of Muslim entry to the US, which prompted the National Park Service to revoke his visa.
He said the US was now “at war with radical Islamic terrorism”, and the “radical ideology” was being “radicalised”.
Trump has not said when he will announce a new strategy to fight the terrorist group Islamic State (IS, formerly ISIS/ISIL) in the Middle East.
His predecessor, Barack Obama, called the threat posed by IS “a global and existential threat”.