Asteroid Threat: Good News, We Have the Technology; Bad News -

"Asteroid Threat? Call the Space Lawyers"
Space.com (April 28, 2009)

"Asteroids that might threaten Earth could pose a challenge beyond the obvious, if nations can't get their act together and figure out a unified plan of action.

"There are currently no known space rocks on a collision course with Earth, but with ample evidence for past impacts, researchers say it's only a matter of time before one is found to be heading our way.

"A swarm of political and legal issues bedevil any national or international response, whether it's responsibility for collateral damage from deflected asteroids or the possible outcry if one country decides to unilaterally nuke the space threat.

" 'The word "unorganized" is spot on here,' said Frans von der Dunk...."

Assuming that an asteroid headed for Earth was spotted, we've got the technology to deal with the problem. The problem is:

• Telling people that an asteroid was going to hit Earth would upset some people
  • And they would sue
• Not telling people that an asteroid was going to hit Earth would upset other people
  • And they would sue
• Reducing an asteroid to the sort of rubble Earth's atmosphere handles every hour is possible
  • But not every national leader would be happy about that
  • World reactions to China's way of dealing with one of its aging weather satellites in 2007, and America's similar action in 2008 give a clue
• Of course, if all world leaders and the United Nations Security council agreed - - -
  • Does anyone really think that would happen?
• Somewhere on Earth, after someone had the unmitigated gall to save Earth, a rock would fall out of the sky
  • Then there would be lawsuits to collect whatever the market would bear in damages

I'm not hopeless about the situation: but this article does look at some of the legal and systemic issues that face us, when astronomers do notice a big rock headed our way.