The tsunami of 2011 demonstrated how far Hawaii already has progressed in emergency preparedness. Even so, we are reminded how much more we need to learn.

Repeated sirens and advisories notwithstanding, there were still people who insisted on approaching the shoreline and even taking leisurely walks there, at the precise moment they should have been seeking higher ground.

Another first instinct exhibited by some families was a poor one: to park in long gas lines or prowl through supermarket aisles for supplies. The brink of disaster is not the time for such preparations. These actions were enabled by the long lead time between the trigger of the devastating earthquake in Japan and the arrival of the shock waves it produced.

The danger here is that, with two tsunamis in two years leaving the islands all but unscathed, the people of Hawaii could develop a jaded attitude about these threats. And this must not be allowed to happen.

The impact on Hawaii consisted largely of boat-harbor piers knocked off their moorings and scattered episodes of damage to boats and other property. Such losses can’t be dismissed lightly, but the horrific video images left an indelible impression of the true toll of a tsunami. The quake, a terrifying 8.9 on the Richter scale, ignited fires and undermined a nuclear power plant; titanic waves scoured Japanese farmlands and left wreckage, death and sorrow in their wake.

And then a smaller temblor, only about 4.5 in intensity but just 12 miles offshore from Pahoa, served as a chilling reminder: It is possible for an earthquake to strike near Hawaii, so close that residents would have little time to prepare for any wave it generates. And that time we would not be "fortunate almost beyond words," to borrow Gov. Neil Abercrombie’s description of Friday morning’s sobering events.

Hawaii should feel encouraged by several elements in the disaster response that worked well. The Pacific Tsunami Warning Center carefully evaluated its data from its system of measurement buoys and issued projections that proved to be spot-on. Abercrombie, Honolulu Mayor Peter Carlisle and other elected officials kept on message and marshaled the emergency teams to keep people out of danger zones until the all-clear.

State and city officials must conduct a thorough postmortem and identify any necessary revisions (various communications channels and social media — Facebook, Twitter and text messaging among them — helped bring them to light).

For example, sirens weren’t universally functional; some residents tracking events also expressed frustration that remote Web cams weren’t being used to better advantage to help monitor neighbor-island evacuation zones.

Hawaii residents and their leaders also should reach out to show kokua to victims of the tragedy in Japan. Hawaii has too many historic, cultural and familial links to that nation to do otherwise. The Red Cross (redcross.org) offers one of the many routes to do so.

Basic human compassion makes disaster relief a moral imperative for the entire U.S. But island residents in particular have a duty to help, because by now we should be persuaded that nature doesn’t play favorites. Hawaii very well could be next, and its people must be ready.