It is the year 2019, and the liberal democratic order in country Z has been overthrown by a new radical movement with strong popular support, led and largely defined by the Ecologists.1
The pressures in country Z had been building for some time. The governing and other major parties had paid lip-service to 'the environment' but were not willing to take what growing numbers of increasingly vocal citizens felt were the really tough decisions on energy, nature conservation, transport and waste disposal. Environmental pressure groups gained in membership, prominence, and influence. New media outlets, especially web-based ones, took on the ecological agenda strongly. Key scientific bodies bemoaned, with little internal dissent, the lack of action to protect both the environment and people's right to live in a healthy environment. Media scares that global warming would, much sooner than anyone had foreseen, turn country Z from a temperate into a tropical country were prominent.
The final demise of the liberal democratic regime came rapidly over four days in May. The events of those days looked familiar to those old enough to have been around for the fall of the Berlin Wall and the eastern European revolutions thirty years before—the daily discrediting and delegitimizing of the major parties and establishment leaders, mass marches by ordinary citizens led by non-establishment figures and civic movements, a sense of unstoppable popular and political momentum, the odd combination of near-anarchy and euphoria at the resignation of the government, and the declaration of a new political system. There was little violence, the national army having retreated to its barracks.
A new, interim government is formed, led by civic movement Ecologists, with a smattering of sympathetic scientists, a prominent journalist, and a dissenter from the old liberal party. Green flags fly alongside the national flag on public buildings. Within a few days, a new Basic Law of the Land—described by the interim prime minister as 'our new constitution'—is published. The Basic Law contains strong environmental provisions, above all—a right of citizens to a clean and healthy environment, a right of future generations to the same, entrenched limits on carbon production, provisions to prevent the long-distance transportation of most foodstuffs, tough limitations on rights to private car ownership, and a description of Zedians as 'responsible citizens of the planet'. It begins with a ringing declaration—'We, the people, on behalf of our children and their children, and of the land and all that live from it, declare this day a new republic built on the timeless foundation of sustainability.'
In that scenario—or in a scenario that broadly resembles it—is the problem of 'green constitutionalism' basically solved? Constitutionalism, after all, is an orientation and a practice which is engaged in setting, clarifying and justifying the basic political rules of the game for a given jurisdiction (mostly, still, countries). These rules of the game and their principles are often set out in written documents which are—with some complicated exceptions—above (mere) politics in the sense of the daily processes of governance. And it is in times of serious political crisis and upheaval, up to and including revolution, that constitutional slates can most readily be wiped clean and new constitutions declared and entrenched.
Governments operate within, and not on, those basic rules. Though the constitution can, in most countries, be amended, it is mostly not easy to do—some combination of supermajorities and popular referendum is often required (in democratic countries) to achieve constitutional changes. So, we have here a case of relatively timeless, well-entrenched, demands for sustainability which cannot readily be overturned or ignored in the day-to-day machinations of the future political and economic life of country Z. At the heart of the question of green constitutionalism, arguably, is the green concern that liberal democratic states (and non-democratic states) will not do what they ought to do to institute sustainability. Placing the necessity of so doing above politics as an unavoidable requirement upon states may, it seems, be a profound and powerful solution.
For several reasons my response is this does not in fact—at the very least...