Questions will always haunt the memory of Hurricane Katrina. The storm caused $108bn of damage and one million people were displaced in scenes America was more used to seeing in disaster movies, not on its doorstep.
Unfortunately, Katrina was not a one-off. Instead, it was part of a global increase in both the prevalence and severity of natural disasters. Disasters such as storms, floods and droughts have increased five fold since the 1970s according to UN figures. Increasing population density and the effects of Climate Change are combining to produce a lethal combination. Next time, the US will be better prepared - but many of the world's most vulnerable communities need better support from those of us equipped to give it. We must not let them down.
Planning for disasters before they happen is essential. Without forethought, even the most well-meant assistance can do more harm than good. After the Rwandan Genocide, bottled water - flown in by aid groups - was left on the runway as there was nowhere for it to go, blocking the arrival of other badly needed supplies.
Great strides have since been made, under the leadership of the United Nations. They have begun to produce guidelines to help response planning for various different major crises - from major disease outbreaks to enormous hurricanes.
When we do work together in harmony, the reduction in suffering can be extraordinary. When the Nepal earthquakes struck earlier this year, many of us working in Disaster Relief and Extreme Medicine feared the worst. Nepal doesn't have the inbuilt resilience of long-term earthquake-proof building regulations, or the resources of the United States to protect its citizens.
But the responses from India and China dwarfed expectations. Although many still lost their lives, the human cost could have been considerably higher. Nepal will take many years to recover, but it could have been decades. Yet there is more to be done to combat the increasing threat of natural disasters.
First, every developed country must make its relief capacities and particular areas of expertise clear in advance, ready to be called upon when disaster strikes. The type of aid that arrives must come in the right quantities at the right time. Britain, for example should work to reach an 'SMT2' level of response readiness - which equates to the ability to build full field hospitals - that befits our wealth and resources.
Second, we need the most effective healthcare response when disaster strikes. Four years ago, I co-founded the Extreme Medicine Conference. The annual conference brings doctors, medical experts and humanitarian workers together under one roof, so that best practice and skills can be shared and our response to disasters improved. This year, the inaugural innovation platform should help kick-start the technological help in diagnosis, communications and practice that could transform the discipline.
Third, we must help developing countries increase their latent structural resistance to the effects of disasters and develop their own response capacities. An efficient way to reduce the impact of a disaster is to ensure that the environment is able to soak up much of the damage - better building techniques and response strategies can make a huge difference to that casualty count.
Inextricably linked to these efforts is the fight against Climate Change. Rising temperatures directly impact the severity of weather-related disasters, and the prevalence of diseases that rely on warmer temperatures to spread, like Malaria. The real solution is to tackle not the consequences of global disasters, but their root causes. Getting serious about natural disasters means, at heart, getting serious on climate change too.
Dr Sean Hudson is a Remote Medicine Specialist and the organiser of the Extreme Medicine Conference. Now in its fourth year, the conference will be held in London from the 26th to the 29th October.