There is a lot about the political philosophy of libertarianism that is appealing. The idea that one should be free to behave as one wishes – as long as it doesn’t harm others – seems to provide a decent balance between allowing people to pursue their own purposes and stopping that pursuit from harming the general interest. That being said, the degree to which libertarianism can be liberating is diminishing with time. This is basically because of both the growing fact of interconnectedness and because of our growing awareness of it.
One example is economic globalization. At one point in time, it would have been considered reasonable to argue that economic activity on one side of the world has no morally relevant effect on the other. Now that markets are more linked, products and capital flow, and awareness of linkages exist, that becomes very difficult to argue. Before, it is as though the chooser was alone in a room with a light switch. It is of no particular moral consequence whether they choose to have it on or not. Now, it is more as though that light switch also reduces the function of the equipment in a hospital across town when it is pulled. Whereas libertarianism previously permitted free choice, the inter-linked example includes a moral obligation to act in a certain way.
Climate change may be the ultimate force diminishing how liberating libertarianism can be. Not only do nearly all of our life and economic choices impact innocent third parties around the world, they also contribute to a problem that will have a huge long-term impact on future generations and the natural world. Arguably, this makes the doctrine of “do what you like but do no harm” impossible to follow in practice.
It is not clear if or how the appealing aspects of libertarianism can be maintained in a world full of important material interconnections. The most plausible answer seems to be a combination of working hard to create situations where multiple moral choices actually do exist (light switches that don’t shut down breathing machines) and accepting those situations where the tradeoffs are real and making a determined effort to choose the least harmful option.