Pessimism has been the defining political mood of 2018. Pessimism fuelled by fears that young people will be the first generation who find themselves worse off than their parents; that gaping regional inequalities are going to widen post-Brexit; that the world will be overtaken by catastrophic climate change; that we are on the brink of an overwhelming instability in the global order not seen since the cold war.

There are certainly reasons to be glum going into 2019. There is not only a growing sense that Britain will be at the mercy of powerful global forces it can do little about. Brexit looms on the horizon, a challenge entirely of our own making that threatens to ensure there is next to no political capacity left for anything else.

But the fug of pessimism too easily distracts us from the eminently solvable nature of many of the challenges Britain faces. All it would take is political leadership, courage and ambition. Here are five ideas within the grasp of any government determined to make Britain a kinder, greener, more equitable place to live in the 2020s.

Rethinking ageing

Our stretched lifespans are an incredible marker of human progress; a just cause for celebration. But not only are we living longer, we are living longer with frightening and debilitating conditions such as dementia that erode our mental as well as physical capacities. Yet as a society, we have given barely a thought to how we care for older people towards the end of their lives in a way that supports them to live fulfilling, rich lives rather than manages physical decline.

This will require profound shifts in how we think about care. But it should begin with a radical reform of entitlements in older age. It is ludicrous and ageist that someone diagnosed with cancer gets free care, whereas most people diagnosed with dementia have to fund their own care. The government should phase in free personal care, funded through progressive taxation. We must also reimagine caring as a high-skill profession, which should start with the government, the biggest buyer of care services, setting higher pay for carers.

The future of work

Just as inventions such as the washing machine have transformed labour markets of the past, so automation and artificial intelligence will continue to transform the labour market of today. We should be wary of dystopian predictions of the end of work; past waves of technological progress have created new jobs to replace the ones displaced. But technology will transform the nature of work, leaving some without the skills they need to adapt, and, left unfettered, will increase inequality.

There has been insufficient thinking about how to improve the quality of work today, let alone in the future. We need to prepare by reforming post-18 education funding so that all young people get the sizable state subsidy that those who go to university do, regardless of which route they pick, and by setting up a reskilling fund to offer one-off grants to those who lose their jobs to automation. Unions should be offered new powers contingent on them diversifying their memberships, currently dominated by older, professional, better-paid workers.

Slowing global warming

Climate change poses an increasingly existential threat to mankind and the time available to stave off catastrophic levels of warming is running out. The government must do more to advocate for global net-zero carbon emissions by 2050, and set out a plan for the UK to produce net-zero carbon emissions before 2050, including bringing forwards the ban on the sale of new petrol and diesel cars to 2030.

Reining in the tech giants

Always-on technology is changing the way we live our lives, from the way we consume news, interact with friends and buy things. But technology has evolved far faster than government’s willingness to regulate. The government should introduce greater restrictions on the way monolithic tech companies operate. Potential options include establishing a legal “duty of care” towards their users to tackle online abuse, obliging providers to publish the algorithms that determine what people see in their feeds and increasing the digital services tax that will be levied on the UK revenue of large tech companies from 2020.

Reinvigorating our democracy

Our majoritarian, two-party system is struggling to cope with a freshly multidimensional political spectrum, in which Brexit has riven both main parties. The quality of political debate has degraded as politicians from both the fringe and the mainstream have grasped at the easy appeal of populism: blaming scapegoats and telling people there are no tough trade-offs.

There may be little appetite for the type of institutional reform, such as a more proportional voting system, that the Observer has long supported. But we urgently need to update electoral law for the 21st century, for example by bringing social media campaign spending within national caps and exploring ways to encourage consensus-building and informed debate into our politics, for example through the citizens’ assemblies used in the Irish Republic to empower people to deliberate and issue recommendations on key issues such as abortion.

The country indeed faces big societal, technological and climate-related challenges going into 2019. But their scale is far from unprecedented. With political leadership and spirit of the sort we saw in the late 1940s, it’s within the grasp of our leaders to ensure Britain can face the future with optimism.