When it comes to so-called "global governance", it's easy to be cynical. Our worldwide institutions – the UN, the World Bank and more – have all let us down. Nation states vie for self-serving positions in the Security Council, while institutions such as the World Food Programme or the UN High Commission for Refugees are left hampered by realpolitik, severely under-resourced in times of crisis.

UN goals flag ceremony
Children pose with a UN Sustainable Development Goals flag outside Number 10 Downing Street Chris Jackson/Getty Images

The optimism that ushered in the UN and its various treaties 70 years ago seems a far cry from the realities of today. Every time I hear of a new UN framework, from the climate change convention to an arms treaty, I can't help feeling as though I've been given an overinflated sense of hope. It's like opening a puffy, air-filled bag of crisps only to find it contains but a few crumbs.

But if we didn't have the UN, we would probably have to invent it. In these troubled times, a sense of hope and, at the very least, the illusion that the world is pulling together is the minimum we need to sustain ourselves. And this weekend there is a big package full of air-inflated hope on offer in the form of the clumsily named Sustainable Development Goals (SDGs) launched in New York by a circus of thousands of civil society leaders, businesses and world leaders.

Their predecessor, the Millennium Development Goals (MDGs) that expire this year, were an interesting exercise in quantifying poverty reduction efforts, but were woefully inadequate: few of the targets were met in practice and many of their design elements were flawed.

The key target (of MDGs) was to halve the number of people living in extreme poverty, which was determined to be those earning approximately $1.25 (£1.90) per day. But that's an irrelevant amount if prices are rising, and it still leaves whole swathes of a population, as it has for more than 50% of sub-Saharan Africa, deeply impoverished.

The SDGs have sought to correct things where the MDGs went wrong. Consequently, there is now a set of 17 goals with no less than 169 specific targets, tackling everything from alleviating poverty to gender inequality to climate change. This is no bad thing.

UN goals flag ceremony
Australian actress Deborah Mailman raises the flag representing Goal 11: Sustainable Cities and Communities Ryan Pierse/Getty Images for Global Goals

What's different about the SDGs is their level of participation in the design. Some have argued that this has left the SDGs so unwieldy as to be meaningless. But I would prefer a consensus of aspirations based on a democratic voice than a target imposed from on high. People would be more likely to buy in to the goals and participate in their delivery.

Unlike the MDGs, the goals also recognise the complexity of sustainable development. You can't just say "reduce CO2 emissions" without considering energy access for the poor; nor can you talk about "economic growth" without an understanding of inequality.

India – where one-third of the world's absolute poor still reside – has had average growth rates of over 7% for the past five years but the absolute poor remain poor. The SDGs talk about equality levels as much as they do about growth. They talk about growth as much as they do about problems of overconsumption. And they address how might get there, too.

The MDGs applied to poor people; the SDGs apply to all of us. This alone is an improvement. None of us are perfect and all countries, rich and poor, have their challenges. It recognises the interconnected nature of the world in which we live.

The biggest flaw, perhaps, is that, unlike previous treaties, the SDGs aren't legally binding. The UN doesn't really do legally binding anymore. Perhaps it recognises that there's not much point, as countries can ignore them anyway. But it is good to have a beacon of hope every now and again, even when it comes in the form of an air-filled packet of crisps, or an aspirational, widely adopted set of UN goals. Right now, I'll take what I can get and park the cynicism.

Deborah Doane is a writer and consultant on new economics and sustainability. She was previously director of the World Development Movement.