"Going green" has more factors in its favor than the mere fact that it's trendy. Renewable resources are both a long and short-term advantage, if managed correctly, and resolve or diminish problems that non-renewable resources generate, such as toxic waste, resource wars, or economic instability. Consider, for example, the fact that gasoline prices go up every time investors worry about "strife in the Middle East". Resources produced in our own country wouldn't be subject to this sort of uncontrollable instability.
However, when evaluating a proposal such as replacing petroleum plastics with polylactic acid, we need to consider all the various factors that inform this proposal:
- There's certain to be a company or group of companies that stand to profit from this transition. Likewise, the companies that control and manufacture petroleum plastics aren't going to be too happy about this.
- Polylactic acid doesn't just appear from nowhere; in the United States, it comes from corn. Using corn to produce plastic, instead of using it for ethanol, or food, will affect the prices of those products.
- Switching to a biodegradable product doesn't address the reason for its use in the first place; in fact, using a biodegradable might give users a sense of complacency, thinking "it's ok, it's green!", using packaging that isn't necessary. If we use less, we waste less.
- Most of the industrial infrastructure will remain in place; we will still be using petroleum-based energy to manufacture and ship these new plastics.
- Polylactic plastics do not have all of the same properties as petroleum plastics. Until a solution is created, polylactics cannot completely replace petroleum plastics.
- We haven't really defined "green"; in fact, no one really has control of this term and what it means. If we're going to designate "green" as a desirable trait, it needs to have some clear definitions associated with it.
True, it IS important for us to investigate opportunities to increase our use of renewable resources, because it's been shown that our nonrenewable resources will eventually run out, and their limited supply causes a chain reaction of negative effects. However, the proposed switch to polylactic acid isn't a clear-cut positive; we would have to thoroughly investigate each of the issues I outlined above, and evalute them on a cost-benefit basis.
I think the most significant impact would be to the price of corn and the production of ethanol; corn is already heavily subsidized by the government, and this entire industry is very complex. Ultimately I would support this transition on ethical, environmental and economic grounds, in the same sense that I support the right to own guns or the right to healthcare; however, the exact way in which these things are implemented may or may not meet my standards.