There are times in life when you bear witness to events and actions that change your outlook thereafter. This past week has provided that for a nation.
Eruptions of applause, the smiling faces of police officers and a wave of relief on social networks punctuated the end of a week in US history that saw the depths to which human nature can plunge, twinned with the fortitude of the human spirit.
Last Monday brought the annual highlight in Boston's calendar round again, for the 117th year.
An occasion that unites people and nations on its streets in a public display of physical strength - its marathon - the ultimate test of human endeavour. But this year, because of its significance, because of its importance to a city it became the target for visceral evil.
Two explosions, two crude bombs allegedly created by two brothers took three young lives and maimed more than 180 others. Injuries so gruesome, so life-changing even the most hardy of medics likened the scenes to a war zone.
Yet in the midst of that chaos and blind terror ordinary people as well as emergency crews ran towards the danger, spurred by an instinct to help, and relieve the suffering of others. Monday evolved into a different kind of test, a test of human strength and kindness.
The following days saw a desperate scramble to find out why and who had done this. Those questions haunted the FBI, as Boston's intense need for a culprit grew.
"We're standoffish people by nature," a Bostonian journalist told me, "but don't screw with us. We will find them, we will recover and next year our marathon will be bigger than ever." Defiant words but a resolve that echoed across the city.
And then the pictures, CCTV of the two main suspects were released - the potential perpetrators now a visual reality, moving freely and calmly, in amongst their victims.
A significant move by the FBI to find their men. Someone would know them. The net was closing in.
But it was Friday when events culminated in yet another death, a dramatic firefight between suspects and police, the shooting of one brother and an intense manhunt for the other.
A city paralysed by a week of terror then deserted of people.
Ordered to stay indoors to protect themselves from an unpredictable terrorist with a seemingly limitless capacity to inflict suffering.
And then he was found, cowering inside a boat in a garden.
A basic, desperate, almost childlike hideout for a man who's resistance to arrest was now weak, his options few, and those intent on his capture showed no relent.
Caught and in custody detectives described their exhaustion yet their victory as spontaneous applause rang out in the streets. Revenge within 4 days was sweet. Relief palpable.
This man now lies in a hospital bed facing charges. He is seriously injured. He suffered a gunshot to the mouth. He can't talk.
He's being treated by the same doctors who a week ago tended to those brutalised by his alleged actions.
He is communicating with police in writing, answering their questions. Why Boston? Why the marathon? Why America? And the families of the dead and the wounded, some of whom now have to learn how to stand, walk and live again, deserve those answers.