If you are not part of the solution, ran a 1960s countercultural slogan, then you are part of the problem. Part of the problem that we face today is that no one thing is more than part of the solution.

In a world of complex connections, the problems, and their possible solutions, are more intricate than ever. This applies particularly to the enduring issue of the environment. Our continuing dependence on fossil fuels contributes to climate change, with the long-term consequence of environmental degradation and political instability in those countries adversely affected by that change. We are all familiar with the problem. But the sheer variety of ways in which technologically advanced societies are dependent on fossil fuels, the fact that we take for granted the ability to travel internationally, and to commute on a daily basis between our homes and our workplaces, plus the growing demand for energy in developing nations such as India and China, make any simple, single solution seem remote.

Could a technological advance cut this Gordian knot? A recent article in Britain's Guardian newspaper suggested that it might. The solution is a network of high-voltage direct-current cables, potentially a practical means of long-distance transmission of electricity. Hitherto, we have relied on alternating-current cables, which lose too much energy to be used over long distances. But scientists working for the European Union claim that modern DC cables could one day allow all of Europe's energy needs to be supplied by renewable energy. These cables will carry solar energy from North Africa, geothermal energy from Icelandic volcanoes, and wind power from Britain and Denmark. When one form of energy is lacking (for instance, when there is no wind in Northern Europe), another will supply the shortfall (there will still be sunlight in the Sahara).

Anything that could enable a shift to renewable energy on a grand scale merits urgent consideration. But this proposed solution to an environmental problem overlooks the related geopolitical one.

The current dependence of the West and other developed countries on fossil fuels is a problem not only because of its environmental dangers but also because the largest deposits of our most vital fossil fuel, oil, are located in countries that are politically unstable and in many ways ideologically inimical to the nations that are the biggest consumers. This latter problem wil0l not be resolved by the EU plan to shift toward renewable energy.

Saharan solar power is vital to the plan. But sunshine-rich North Africa, no less than the oil-rich Middle East, is a politically unstable region. The government of Algeria has said that it "aims to export 6,000 megawatts of solar-generated power to Europe by 2020." But it is doubtful that Algeria's Islamist militants, who have continued to pursue a low-level insurgency since the end of full-scale civil war in 2002, share this ambition. The EU plan requires a political stability that cannot be guaranteed in the uneasy 21st century.

From a geopolitical perspective, then, it is surely desirable that in unstable times nations strive as much as possible for self-sufficiency. This is not an argument for isolationism. But the EU, at least, as an increasingly close-knit grouping of broadly like-minded countries, with similar political assumptions, social concerns and economic priorities, should ideally strive to be able to generate the energy it needs on its own territory.

Yet this raises questions of practicality. Solar panels in Spain would be politically more secure than solar panels in Algeria, and some are already in place; but Spain lacks the vast deserts of North Africa. Without the key contribution of Saharan solar power, geothermal energy from Iceland (an EU country in all but name), Northern European wind power or other renewable sources may not be able to provide a volume of energy sufficient to satisfy the continent's needs.

Geothermal energy is perhaps the most promising of the alternatives since it is thought that the amount of energy currently drawn from such sources is a fraction of the possible total. Indeed, this is a matter that might also be of relevance to Japan, which despite the widespread subterranean heat that warms thousands of onsen, generates less than 1 percent of its energy from geothermal sources. But for Europe and elsewhere, the technology to exploit geothermal sources fully is, sadly, still in the future.

The EU plan certainly has many virtues. It has a firm technological basis and it sees the importance of diversification; it does not pretend that any one energy source could supply all our needs. But we cannot assume that technological advances will solve our problems without tackling the political disagreements that are so pervasive today. We need to learn again that pragmatic solutions to practical problems are not enough. We need also a more just and equitable answer to the political questions of our century.