When disaster strikes, brands can quickly find themselves in the social media crosshairs. Just ask BP, which found itself under attack when a horrible oil spill caused a PR nightmare the likes of which only a crisis PR firm could enjoy.

But with consumers and activist groups becoming more sophisticated in their use of social media, brands are increasingly discovering that a social media crisis can strike at any time — for good reason, or no reason at all.

Another oil company, Shell, is learning that the hard way thanks to a fake Arctic Ready website, modeled after a section of Shell’s own website, which has gone viral. The now-viral brand hijacking campaign, which appears to incorporate a fake Shell Twitter account, is the work of Greenpeace and The Yes Men, which don’t need a real oil spill to justify creating a ‘social media oil spill’ of their own, catching their target, Shell, off-guard.

So what should the oil giant do? Observers have a variety of ideas, some more specific than others. One suggested Shell respond with a spoof Greenpeace website; another merely stated that Shell needed to respond so as not to appear “out of touch.” Is either a good idea, though?

Analyzing the situation.

Shell, as one of the world’s largest oil companies, is a frequent target of activist groups like Greenpeace. So the environmental group’s latest attempt at hijacking the brand of a company it doesn’t like shouldn’t come as a surprise to Shell. The bad news for the company: the campaign is attracting attention. It’s fairly clever if not innovative, and it’s arguably most effective because it turns Shell’s own marketing collateral against it.

But there’s nothing to suggest that this campaign has longevity like, for instance, the backlash against BP when it was at the center of a real oil spill. Yes, some people are going to find it amusing to poke fun at Shell by creating their own copy for Shell ads. But the average person is not going to be making arcticready.com his or her homepage. The site will, for most, likely be a temporary amusement.

Assessing the impact.

Every company facing a social media crisis should assess the realistic impact of that crisis. Typically, this should focus on key metrics. Some, like brand reputation, are more subjective. Others, like revenue, are quite objective.

Shell, like or not, is involved in the production and sale of a product that just about everyone uses in some form or another. It may not win any popularity contests, but it doesn’t have to and it knows that. Without a situation that makes Shell look really, really bad (again, like a real oil spill), there’s nothing here to indicate that Greenpeace’s Arctic Ready campaign will have any impact on Shell’s brand or sales.

Put simply, if you didn’t care about Shell before, you probably won’t now, and if you didn’t like Shell before, you probably can’t like it any less.

Knowing when to fight fire with fire.

So what should Shell do? When a self-inflicted disaster sparks a social media backlash that truly threatens a company’s brand reputation and sales, fighting fire with fire (read: mounting a strong response) may be the only option.

But when facing a troll-like campaign that isn’t backed by anything that would illicit strong, long-lasting negative emotion from the average consumer, fighting fire with ice (read: not saying anything) may be a far better approach. After all, operators of blogs and online communities have long understood the wisdom of “Don’t feed the trolls” and now that brands are far more exposed to user-generated content and online communities — whether they like it or not — they too would be wise to recognize when they’re being trolled.