The past 37 years have been replete with U.S. interventions. Some have succeeded, such as our actions in Grenada (1983), Panama (1989), the Persian Gulf War (1991) and the Balkans (1995-2000). Some were awful blunders, such as the attempted hostage rescue in Iran (1980), landing the Marines in Lebanon (1982) or the Somalia intervention (1992-94).

Some worked in the short run, but not the longer term - such as the occupation of Haiti in 1994. Others still hang in the balance, such as the wars in Afghanistan and Iraq, consuming hundreds of billions of dollars and wrecking thousands of American lives. Along the way, we've bombed a few tyrants such as Saddam Hussein and Gaddafi himself, operated through proxies in Central America, and stood ready with fly-overs, deployments, mobility exercises and sail-bys across the globe.

• Understand the national interests at stake, and decide if the result is worth the cost.

• Know your purpose and how the proposed military action will achieve it.

• Determine the political endgame before intervening.

• Get U.S. public support, obtain diplomatic and legal authority, and get allies engaged.

• Avoid U.S. and civilian casualties.

• Once you decide to do it, get it over with.

Protecting access to oil supplies has become a vital interest, but Libya doesn't sell much oil to the United States, and what has been cut off is apparently being replaced by Saudi production. Other national interests are more complex. Of course, we want to support democratic movements in the region, but we have two such operations already underway - in Iraq and Afghanistan. Then there are the humanitarian concerns. It is hard to stand by as innocent people are caught up in violence, but that's what we did when civil wars in Africa killed several million and when fighting in Darfur killed hundreds of thousands. So far, the violence in Libya is not significant in comparison. Maybe we could earn a cheap "victory," but, on whatever basis we intervene, it would become the United States vs. Gaddafi, and we would be committed to fight to his finish. That could entail a substantial ground operation, some casualties and an extended post-conflict peacekeeping presence. [my emphasis]

... if we want to get rid of Gaddafi, a no-fly zone is unlikely to be sufficient - it is a slick way to slide down the slope to deeper intervention.

In Libya, we don't know who the rebels really are or how a legitimate government would be formed if Gaddafi were pushed out. Perhaps we will have a better sense when Secretary of State Hillary Rodham Clinton meets with rebel leaders, as she is scheduled to do this coming week. In a best-case scenario, there would be a constitutional convention, voter lists, political parties and internationally supervised free and fair elections. But there could also be a violent scramble for authority in which the most organized, secretive and vicious elements take over. We are not well-equipped to handle that kind of struggle. And once we intervene, Libya's problems would become our responsibility. [my emphasis]

Given these rules, what is the wisest course of action in Libya? To me, it seems we have no clear basis for action. Whatever resources we dedicate for a no-fly zone would probably be too little, too late. We would once again be committing our military to force regime change in a Muslim land, even though we can't quite bring ourselves to say it. So let's recognize that the basic requirements for successful intervention simply don't exist, at least not yet: We don't have a clearly stated objective, legal authority, committed international support or adequate on-the-scene military capabilities, and Libya's politics hardly foreshadow a clear outcome.