Mr Trump copped wide criticism for his accusations on Twitter the Federal Bureau of Investigation spent too much time trying to prove Russian collusion with the 2016 Trump campaign and missed a crucial warning accused former pupil Nikolas Cruz was a danger to others.
The FBI admitted it failed to investigate a warning Cruz possessed a gun and a desire to kill.
But the FBI was not the only one to miss signs of the deteriorating mental state of Cruz. He was reported to have been investigated by police and state officials as far back as 2016 after slashing his arm in a social media video, saying he wanted to buy a gun. Authorities determined then he was receiving sufficient support.
After the event, many agencies are saying Cruz should have raised red flags and all the signs were missed. In a country the size of America, you can nearly understand why not every call about strange behaviour gets checked.
Cruz, who faces 17 counts of premeditated murder, legally bought the AR-15 semi-automatic assault and ammunition used in the shooting after passing a background check. At 19, Cruz cannot legally buy and consume alcohol, yet laws in the US mean he can buy guns.
The school shootings are not a new phenomenon. Former president Barack Obama faced the same resistance after he and his administration tried to change gun laws.
Last week's massacre followed several other school shootings this year and has again inflamed the country's long-simmering debate between advocates for gun control and gun ownership.
The powerful gun lobby, the National Rifle Association, pours millions of dollars into the campaigns of politicians to protect its right to bear arms, something guaranteed in the American constitution.
It has been pointed out after the Marjory Stoneman Douglas High School shooting that when the constitution was drawn up, the arms were restricted to muskets and pistols filled with powder and shot - not semi-automatic rifles designed to kill at an indiscriminate rate.
However, there is now hope a younger generation of Americans will continue to push for change after the latest tragedy.
Thousands of protesters during the weekend demanded an immediate response from politicians. Many of the demands came from young survivors who witnessed the shooting of classmates and friends.
Teenage survivors criticised politicians for taking donations from the NRA, one calling out ``shame on you'' during a rally.
A group of pupils from the high school announced they are planning a march on Washington DC on March 24 to demand action on guns. The group say they are determined to make a difference. Let us hope they are correct.
America seems fascinated with guns. A mass shooting usually leads to calls for schools to arm themselves to make themselves and their pupils safer. As one young person pointed out at the weekend, Cruz would have inflicted far less damage if armed with a knife instead of a semi-automatic weapon.
The true test now will be whether the young people will be taken seriously enough on Capitol Hill by politicians facing re-election this year. Young people can often be ignored because they are not yet voters.
So far, lawmakers have been offering thoughts and prayers for the families as they grieve, actions which go nowhere near solving the problem of arming people who intend to kill others.
The school pupils say they are marching for reasons other than school killings. It is about attacks in movie theatres, concerts and nightclubs. These types of killings cannot be allowed to happen again.
