Rescuers and media representatives from out of state, many of whom thought Oklahoma was a musical or still 19th- century cowboy territory, were surprised by the smooth organisation of the rescue operation and the warmth and politeness of a people hit by tragedy.
It is, everyone agrees, the end of the age of innocence in a state where terrorist attacks, until 19 April, were inconceivable. A "do not leave baggage unattended" announcement at the city's Will Rogers airport as I left, so routine to us, raised eyebrows among the locals and symbolised the leap into the new reality. So did the pilot's announcement that the control tower had been evacuated because of a bomb threat and we should disembark.
Highly religious, in the heart of the "Bible Belt", Oklahomans are already concentrating on the "blessings" they believe the tragedy has brought. They cite the tremendous rescue effort, in which local firefighters were joined by search and rescue teams from all corners of the US. The power of the blast meant they found no one alive after 10pm on the first night but they never gave up while there was a glimmer of hope, using sniffer dogs and removing rubble by hand.
Then there was the overwhelming wave of popular solidarity. With the area of the bomb site cordoned off, people queued for hours to give blood and began donating money, food and clothes at designated pick-up points.
One Oklahoman, hearing of the need for dog bootees because sniffer dogs were cutting their paws on glass and debris, spent hours on the telephone to Alaska until he found a manufacturer of paw-wear for huskies.
"Texans have an image and they feed it," said a local KTOK radio hostess, Carole Arnold. "We were ambiguous. We didn't know who we were. We have found an image. Now, we Oklahomans know who we are." Not since the Depression and the 1930s westward migration from the "dust bowl," had "Okies" felt such unity and solidarity. "I'm proud to be an Okie" T-shirts sold out.
Apart from the troubles of the Thirties, the bombing was the biggest event here since the city was created in the 1889 land rush. On 22 April that year, settlers raced into the region in wagons to hammer stakes into the ground that would allow each to claim 160 acres. Those who jumped the gun were labelled "Sooners", giving birth to Oklahoma's nickname as "The Sooner State".
Comparing the tragedy with the JFK assassination or the 1986 Challenger spacecraft explosion, Robert E Lee, columnist of the Daily Oklahoman, wrote: "For Oklahomans, April 19 is the before-or-after date from which all events will be remembered.''
Infected by the dignity of the locals, the world's media were better behaved than anyone could recall at such a disaster. As a result of media discretion, we were welcomed as never before, even fed for free by the Salvation Army at the site.
When a photographer and I walked into a main-street bar after finishing our work, we were met with a spontaneous burst of applause. At a restaurant one evening, where seven representatives of the British press were dining, seven large Glenlivets appeared at the table "from the gentleman at the bar". Choosing the drink on the basis of our accents, he said he wanted to thank us for telling the world of Oklahoma's grief.