The Sustainable Development Goals, the subject of this week’s World Economic Forum meeting in New York, cannot be met unless we address the fate of the world’s 20 million refugees and 60 million displaced people.

When the goals were adopted by the international community in 2015, they represented a clarion call to include – not just some – but all of the world’s poor, illiterate and sick – the most vulnerable of whom are those exiled from their homes, and often their countries.

In particular, as Professor Klaus Schwab reminds us in an article coinciding with this week’s Sustainable Development Summit, the Global Goals were a solemn declaration by the entire international community. They included a promise to every girl and boy that by 2030 they would be guaranteed, not just a quality primary education, but a secondary education too. But today, half the world’s refugees and displaced children do not go to school – and many more will see their education interrupted and will never get the qualifications they need to thrive in tomorrow’s workforce.

Not only are there 7 million displaced Syrian children and more than 1.5 million displaced Iraqi children as a result of civil wars in their respective countries, in recent months, 500,000 have been displaced from South Sudan into Uganda and another 500,000 are on the move in the Central African Republic. And as I write, more than 250,000 children have left their homes in Myanmar and been forced out onto the seas – many of them now in Bangladesh. Thousands of them will never enter a classroom again.

With children cheated out of first a home and then an education, 2017 will go down in history as the year when – even as the crisis worldwide worsened – society’s youngest and most vulnerable members were all but forgotten as public attention moved elsewhere. The story of their suffering has fallen out of the news, TV cameras have moved on, and our once loud cries for action have gone quiet.

This week’s World Economic Forum Sustainable Development Summit in New York is taking this new reality into account, starting its sessions with a debate on the fate of children trafficked out of their home countries. And the millions who are displaced are not just at risk of trafficking. Every day, girls are forced in to early marriage, boys rounded up to join child militias, and boys and girls bonded into child labor – almost none of whom ever return to school.

Image: UNHCR

So meeting the Sustainable Development Goal of an inclusive and quality education for all by 2030 requires a strategy that answers the pleas of the displaced and refugee communities holed up in the world’s middle income countries.

Yet caught between humanitarian aid that has to focus on basic minimums necessary to live such as food, shelter and medicine, and development aid which is planned over years and slow to respond to crises, education spending is often the first to be diverted and the last to be prioritised when disaster strikes.

This gap in provision led, nearly two years ago, to the historic decision at the UN World Humanitarian Summit to create the Education Cannot Wait (ECW) fund under Yasmine Sherif. Charged with developing a plan to educate out-of-school refugees and displaced children, it is now operating in and around Syria, Iraq, Yemen, South Sudan, Chad and other parts of Africa.

But this week’s UN General Assembly coincides with the arrival of a jarring reality: cash pledges have not kept pace with ever-growing needs. Commitments made at pledging conferences are but words – a reminder of the gap between rhetoric and reality, and a painful truth for millions of children.

Innovative initiatives such as those pioneered by ECW stand as the best chance to slow what has become the largest refugee crisis since the close of the Second World War. But the needs of these children left out and left behind far exceed any funds ECW has at its disposal. So it is up to us to act.

From Syria to the Caribbean, infrastructure can be rebuilt – roads, hospitals and schools made anew. But what about knowledge lost? Only by acting today to ensure a generation is learning and not lost will we provide a foundation for reconstruction and unlock the hope that all – and not just some – children deserve.