Should pregnant women be banned from smoking?

In several recent posts, Dan Kuehn advanced the notion that "the future" is, in some sense, an autarkic regime... Basically, that people in the future simply aren't able to trade/negotiate with us in a way that materially affects our decisions today. Future generations are thus unable to provide the normal market signals and incentives, which would impact our behaviour on matters that stand to directly impact them. (E.g. "We'll compensate you for investing in this technology today, as we'll desparately need it fifty years from now"; "Stop this activity as soon as possible, or we'll sue you for ruining our habitat"; etc).

This sparked off an interesting back-and-forth on, not only whether "autarky" was the correct term to use in this case, but also on whether characterising things in this manner significantly alters the way that we already think about making provisions for / sacrifices on behalf of future generations. For the record, I tend to agree with Bob Murphy that "autarky" isn't technically the right term to use, because it is simply the laws of physics that prevent the future from being able to trade with us. (Contrast, say, the autarkic regime of North Korea, which is physically able to trade with other nations, but has embarked upon a bizarre policy of self-sufficiency because of political and institutional settings.) However, I do think that Daniel's framing was useful because it serves to emphasise the remorseless, uni-directional march of time and how this should inform our policy decisions.

Now, I'm pretty interested in the intemporal trade-offs, as some of you might have guessed from my numerous posts on climate change and, more recently, sustainability. In that light, I left a comment under one of DK's "the-future-is-autarkic" posts... Effectively, the discussion reminded me of an Amartya Sen article that he wrote in support of smoking bans. The position that Sen took was interesting, because he partly appealed to the ethical distinction between a smoker's past and present self, and the inability of these two to negotiate with each other:

Unrestrained smoking is a libertarian half-way house[*]

[H]ow should we see the demands of freedom when habit-forming behaviour today restricts the freedom of the same person in the future? Once acquired, the habit of smoking is hard to kick, and it can be asked, with some plausibility, whether youthful smokers have an unqualified right to place their future selves in such bondage.

Thus, Sen was making a normative argument based on the idea that we aren't always equally "free" to make decisions when it comes to smoking. It's much easier to start the habit than it is to stop and I doubt that any plausible arguments could be made to the contrary. In the Wordsworthian sense, the young smoker is the father of the man that follows him... and yet the latter is far more constrained in his choices than the former. While certainly interesting, this is not what I want to discuss today, however -- not least because there are some very murky waters to tread when it comes to putting boundaries on personal freedom.

Here's another poser for you then: Instead of focusing on an individual smoker's freedom to do to unto themselves as they wish (consequences be damned), should pregnant women be allowed to smoke?

I ask this question after reading about a new British mother who smoked an astonishing 3,500 cigarettes during her pregnancy. This special individual not only exposed her baby to (apparently) six times the safe level of carbon monoxide, but -- surprise! -- successfully ensured that her child was borne underweight and premature. God only knows what medical surprises await this kid as the years roll by... However, I'll offer even money to anyone willing to bet on the mother's own professional prognosis:

I think it was my right and I don’t believe it was hurting Lilly. It’s making the baby use its heart on its own in the first place, so that when it comes out, it’s going to be able to do them things by itself. Where’s the proof that it’s so bad to smoke? - Charlie Wilcox, M.D. (not) and candidate for new mother of the year.

"I'm, like, making the baby's lungs stronger and stuff, innit."
LOL

(Source: Daily Mail via 2oceansvibe)

Is this not the most clear-cut case of a negative externality that you can imagine? Why do we -- for the most part anyway -- endorse smoking bans in public places and yet permit such direct offences to persist in the case of mother and child? Surely there is no logical consistency?

Of course, you could probably extend this argument to parent-offspring relationships in general. If secondary smoke is harmful to strangers in public places, why is it fine for parents to smoke in front of their kids in private homes? Again, there is a strong inconsistency from a purely logical perspective.

I'm interested to hear the libertarian take on this. Is the simple libertarian answer that the child would sue her mother for health ailments, emotional suffering, etc once she reaches the requisite age? [Side note: Does anyone know of such a case?] More plausibly, perhaps children are expected to negotiate with their parents about where and when they smoke in each other's company? (I say "plausible", but that still leaves the uncomfortable period when the toddler or young child is powerless to negotiate on anything resembling equal terms.)

Two caveats before any comments:

1. This is meant to be a thought exercise more than anything else. I'm not making any claims on the practicalities of policing the smoking activities of pregnant women. I'm simply interested in normative ethics at present.
2. Yes, I am discussing a particularly reckless type of parent here. I know that most people are inestimably more responsible than dear Ms Wilcox above. However, I've seen enough pregnant women smoking to know that it happens... Say nothing of smoking in the direct presence of toddlers, which is far more widespread. The point here isn't to examine what most sensible and loving parents would likely do, but to think about how we can best protect kids that are marginalised by the stupid behaviour of their parents. 

[*] Those of you who can't access the original Financial Times article, can read (most of) Sen's text of here.