It wouldn't be quite true to say that John Armstrong walked out of the bombed lobby of the Marriott without a scratch. But almost.
There's a small butterfly dressing on his forehead covering a 1-inch gash.
"The nurse at the embassy told me I cheated death," he told CBS News. "I don't understand it."
It is astonishing. He was only yards from the biggest terrorist bomb in Pakistan's history when it exploded.
Armstrong is an education aid worker from upstate New York, and a single father who had just arrived in Pakistan to start a new job. He had fought to bring his 11-year old son, Jonathan, with him even though the U.S. government considers Islamabad a dangerous post.
The two were living in the Marriott Hotel waiting for new housing.
"My son was invited out to visit a new friend, whose parents I hadn't even met. I hesitated, but thought the company would be good for him so I said he could go - which was very lucky, really. Otherwise we would have been in our room when the bomb went off," Armstrong said.
Instead, Armstrong was down at the hotel's main entrance chatting with the doorman when they saw a large truck ram the security gate.
Then there was a small explosion and he watched as hotel guards ran toward the truck.
"I didn't know where to go. I didn't know if I should go out on the street or just walk as far away as I could get or what I should do," he recalled.
It was surreal, he says, because all it took so long. He even had time to call a friend who's with U.S. Embassy security on his cell phone. They told him to head to the back of the hotel.
As Armstrong turned away, he saw a second explosion in the truck's cab, which the police now say was the suicide-bomber driver detonating a grenade.
"A few seconds later there was just this huge shockwave," he said. "I don't know if I was knocked unconscious or how long I laid there. I was hit with what I think was flying glass from the lobby fish tank. When I got up I was soaking wet and I remember these fish flopping around on the floor."
His first thought was for Jonathan.
"I reached for my cell phone because it was still glowing in the dust, but I couldn't make any calls because the screen was blank," he said.
Improbably, though, he could receive them - and within seconds, his friend was back on the line, telling him to get to the rear of the hotel in case of a secondary explosion.
Dazed, but able to walk, Armstrong found a whole group of shocked and injured hotel guests being led to safety through the kitchens.
Then he made the call to reassure Jonathan.
"He worries about me like I worry about him and I was concerned that he would be frantic," Armstrong said.
In the hospital, among the dead and injured, Armstrong said he was treated with embarrassing kindness.
"They wanted to make me a priority in treatment because I was an American. It was wonderful, but I just didn't feel I could accept it," he said. "There were people there with much worse injuries than mine."
Armstrong's last posting was in Kabul, where he was not allowed to have Jonathan with him. It was too hard - for both of them. They came to Pakistan determined not to be separated again.
But, having survived the worst terrorist attack in the country's history, will John Armstrong stay?
"I don't know," he said. He clearly loves this part of the world and believes he can help Pakistan reform its education system.
"The bombing has left me feeling less secure here, not knowing where I am safe and where I am not."
While the U.S. Embassy re-assesses the security of its staff in the wake of this bombing, Armstrong is concentrating on making Jonathan feel safe and stable.
"I'm glad he didn't see me right after the bombing because there was so much blood from my head wound. When eventually he did see me, he said 'Oh it doesn't look that bad,'" Armstrong noted.
And the priorities and preoccupations of any American 11-year-old boy have helped, too.
"We lost everything in our room," Armstrong said. "It was a burned out shell, but someone has loaned Jonathan a Game Boy - so that's made him happy."