Via Greenpeace International and as published in The Guardian on the 18th of April 2013.

Last year $1.75tn was spent on the world's military, according to new estimates released this Monday by the Stockholm International Peace Institute (SIPRI). Seems like a lot? Let me put this into perspective. This amount is the equivalent of Canada's GDP or twice the GDP of the Netherlands.

Nato members together spent a trillion dollars on the military and despite a significant 6% decrease, the US remains firmly in the lead, accounting for about 40% of the global amount. With a considerable percentage of citizens' taxes both in America (where it's up to 47%) and across the globe going towards military expenses, surely people are entitled to question whether this is money well spent to ensure security. And how this spending is more justified than, say, investing in renewable energy, health care and education.

Consider this: every day 19,000 children under the age of five die around the world, mainly from preventable causes. The costs of reducing mortality rates by two-thirds, improving maternal health as well as combating Aids, malaria and other major diseases, are estimated to be $60bn (£39bn) a year. Meanwhile, $60bn is approximately the cost of buying and operating two nuclear ballistic missile submarines. The estimated total cost of achieving the six of the UN's millennium development goals related to poverty, education and health – eradicating hunger, universal primary education, child mortality reduction, disease prevention– is $120bn annually in additional resources, a fraction of what is spent every year on militaries.

We at Greenpeace join the outcry against excessive military spending. Rather than spending money preparing for conflict, governments must focus their efforts on avoiding conflict and achieving sustainability and equity in their countries.

Climate change is a major driver of conflict and threat to international and national peace and security, putting billions of people's future in jeopardy. It is not often the case that we find ourselves in agreement with the military and intelligence communities, but when it comes to the security implications of climate change, it seems we may have some similar concerns. In May 2012, US Secretary of Defence Leon Panetta said: "Climate change has a dramatic impact on national security: rising sea levels, to severe droughts, to the melting of the polar caps, to more frequent and devastating natural disasters all raise demand for humanitarian assistance and disaster relief."

These impacts of climate change are already being felt. Climate change and a carbon-intensive economy are already responsible for 5 million deaths each year. By 2030, deaths could total 100 million. This is already costing about $1.2tn a year, which could double by 2030 if global temperatures are allowed to rise. So why is it that governments carry on spending $105bn a year on nuclear weapons, rather than diverting the amounts to mitigating the risks of the true WMD – "weather of mass destruction"?

Governments intent on spending taxpayers' money are fuelling the problem, rather than the solution. A new report by the International Monetary Fund (IMF) reveals that worldwide subsidies to fossil fuels total $1.9tn annually. Almost 9% of all annual country budgets are spent on supporting oil, natural gas and coal industries. Subsidies result in overconsumption of dirty energy, which fuels climate change. Eliminating subsidies would lead to a 13% decrease in global energy related CO2 emissions.

Moving away from fossil fuels and investing in renewable energy is the world's best hope for avoiding the most serious impacts of climate change. In 2011, renewable energy provided more than 30% of new electricity production globally, up from less than 5% in 2005. In 2012, investments in renewable energy approximated $250bn – which employed 5 million people worldwide, a win-win situation. An energy revolution in the power sector – moving away from climate-destroying fossil fuels and dangerous nuclear power – would require additional annual investments of $280bn – investments that would not only pay back financially but would significantly reduce the security threats resulting from climate change.

More than $3.5tn is spent annually on the world's military and on subsidising fossil fuels. We can no longer stand by and allow governments to spend recklessly on the wrong things, when so many right things remain neglected. Eradicating poverty and child mortality, and mitigating the destructive impacts of climate change could all be achieved if governments got their priorities right.