But the bombings happened in the heart of a world-class medical cluster. And local hospitals were already bracing for a flood of patients — though they were expecting dehydrated runners, not blast and burn victims, some of whom had lost limbs.

“If there was anything fortunate, it was the geography, because the finish line of the Boston Marathon is smack dab in the middle of five Level One trauma centers,” said Steve Epstein, an emergency physician at Boston’s Beth Israel Deaconess Medical Center and a spokesman for the American College of Emergency Physicians. “Boston is sort of known as a medical mecca. We certainly have resources in terms of personnel that perhaps other communities don’t have.”

And that means even after a decade of emergency planning post Sept. 11, the medical prowess on display in Boston would not necessarily be duplicated if the attack occurred in another U.S. city.

“It’s very important that people not high-five one another and say, ‘This is how good we are,’” said Art Kellermann, an emergency medicine expert and policy analyst for Rand Corp. “It could’ve been a different story. … We’re still struggling to get America’s hospitals to be properly organized … to handle a mass casualty event.”

In the immediate aftermath of the explosions, the wounded began flooding into hospitals like Massachusetts General, Beth Israel, Brigham and Women’s, Tufts Medical Center, Boston Children’s Hospital and Boston Medical Center — all a short drive from the blast site and considered among the most prestigious in the nation.

Doctors and nurses were also on-site at the marathon finish line, ready to treat runners for exhaustion, dehydration or the more routine kind of injuries that can occur in a 26-mile race. Instead, they treated victims of explosions.

Epstein said the relatively smooth response in Boston thanks, in large part, to its abundance of medical resources, could serve as a conversation starter about whether the nation is willing to pay for excess capacity in hospitals. “Hospitals these days have so many financial pressures that are on them to maintain full capacity at all times … that there’s relatively little excess capacity within the hospitals to take a big influx of patients,” he said.

Massachusetts state Sen. Richard Moore, a former Federal Emergency Management Agency official, said there is no question the cluster of hospitals saved lives. “It’s very possible that some patients would have bled out had they not been close enough to treatment,” he said, adding the organizers of future large-scale events might have to build a terrorism response into their planning and budgeting.

Massachusetts General Hospital’s chief of trauma surgery, George Velmahos, made clear that his center is perhaps singularly ready to handle an influx of patients like the one that occurred Monday.

“I think it’s a function of this hospital that it can avail endless resources in the care of the trauma patient,” Velmahos said at a press conference broadcast by CNN. “Trauma in general is extremely challenging because so many specialists need to be pulled over. … Really, this hospital has the ability to pull all these resources to the bedside of the trauma patient. So the greatest challenge that exists, which is to have all the specialists available, is really no challenge here.”

Kellermann noted that treating blast victims requires an expertise in intricate procedures that isn’t always widely available in cities without top-notch trauma centers. But he added that’s beginning to change because many U.S. medical personnel have spent time in Iraq and Afghanistan. “That experience is beginning to percolate in the American trauma community.”

The American Hospital Association notes that all hospitals have “emergency disaster plans” on their books, and many undergo a “vulnerability analysis” to prepare for different types of emergencies. For example, hospitals in tornado alley prepare differently than hospitals in large urban areas that host big events, the AHA said in a statement to POLITICO.

Massachusetts Hospital Association President Lynn Nicholas added that all hospitals in the state have emergency preparedness coordinators and processes. “The value of that preparedness was demonstrated as hospitals performed their duties with excellence and dedication” after the marathon attack, she said.

But while Boston stands out, other communities can maximize their own preparedness for the tragic and unexpected, said Massachusetts General’s medical director for emergency preparedness, Paul Biddinger.

“The preparation and practice are within reach of any facility, irrespective of their clinical capabilities,” he said. For instance, emergency response officials in Boston helped distribute patients evenly among local hospitals, easing the strain on each one. And that’s a function of planning, not of resources, he said.

Kellermann noted that had the city not been in a state of readiness, even Boston and its world-class hospitals might have fared worse. “American hospitals, by and large, don’t routinely prepare for this — certainly don’t practice no-notice drills the way colleagues in Israel do,” he said. “Three cheers to Boston for defying that, in part, perhaps because it was race day. I don’t believe we have any margin for complacency.”