There are certain iconic moments that prove to be turning points in history, where the momentum swings towards change.
These are marked by symbolic events that crystalize public opinion, influence investor sentiment or lead to political upheavals.
The financial crisis in 2007-08 that ushered in policy change to limit investment risk, the Arab Spring and calls for reform or the Fukushima disaster and the upsurge in global opposition to nuclear power are all such moments.
These are defining crossroads offering us the chance of renewal. The race to save the Arctic is another such moment.
Oil major Shell is making a reckless push into the Alaskan Arctic, blind to the logic that sees melting sea ice as a stark warning of climate change, not a business opportunity.
Ironically, it is Shell that has now warned Greenpeace of potential legal "proceedings," claiming that recent protests against its Arctic drilling plans "have posed a real risk to Shell retailers... and the general public".
But let's look at who is really endangering the public's safety, because watching Shell try to explain why its drill ship, the Noble Discoverer, recently lost its mooring in the sheltered Dutch Harbour is really no joke.
Shell officials downplayed the embarrassing incident by claiming the ship never ran aground, but photos and eyewitness statements tell another story.
After spending $4.5 billion on its offshore Alaska program, Shell will not be easily dismayed, however, by setbacks such as lost moorings.
It is trying to circumvent environmental laws in order to start drilling in the Chukchi and Beaufort seas in coming weeks.
The company has asked the U.S. Environmental Protection Agency (EPA) to loosen air pollution requirements for the Discoverer drill rig, as the aging rig cannot meet modern emissions requirements.
The oil polluter continues polluting.
Shell's production has been decreasing for the past 10 years -- with the exception of a 5 percent increase in 2010 -- so the company is desperate to book new reserves and bolster its share price. Accidents are prone to happen in such a rush.
A series of construction delays on its oil spill containment system means Shell is struggling to meet a deadline to gain U.S. federal certification.
This is important given Shell's track record.
In December, in Nigeria, the company spilled an estimated 40,000 barrels of crude into the Gulf of Guinea and regulators have told parliament that Shell should pay a $5 billion fine for the spill at its offshore Bonga field.
Shell says it will challenge the fine, arguing it responded to the spill with "professionalism".
But, will Shell's form of professionalism prevent a spill in the remote Arctic, a region not only home to Indigenous people and wildlife, but a place where hurricane-force winds, massive sea swells and sea ice are all facts of life?
Shell Mexico president Marta Jara describes it like this: "Conditions to drill the Arctic are more difficult than to arrive on the moon".
Shell is still prepared to risk it though, expecting that in 2050 some 60 percent of world energy demand will still be met using fossil fuels, some of which will be sourced in "difficult locations".
That prediction resembles a future energy scenario that Shell itself describes as a "scramble", similar to a vision of the future which the International Energy Agency says would lead to around 4°Celsius of global warming in the long term.
This could result in catastrophic climate change, leading to sea level rises, drought, extreme weather, hunger, water shortages and inevitably, forced migrations.
Essentially, Shell's business model indicates it has abandoned all hope of a stable climate and is banking on climate change.
Greenpeace is resisting this.
In September, we will present an ambitious United Nations resolution aimed at creating a global sanctuary in the high Arctic, placing it off limits to oil companies such as Shell, to industrial fisheries and military activity.
We are calling on political leaders to make a choice because what we, as a global community, do with the Arctic will ultimately define the world we wish to live in.
In the years to come, when we look back at the lost mooring of a Shell drill ship, we can say that this was when we lifted our collective anchor and set course for a green, sustainable and peaceful society.
This must be our turning point.
Kumi Naidoo is the Executive Director of Greenpeace International
Follow Kumi Naidoo on Twitter: www.twitter.com/kuminaidoo