U.S. president Barack Obama was able to please conflicting audiences with his Monday night speech at the National Defense University explaining U.S. policy in Libya.

Neo-conservatives, such as William Kristol and Robert Kagan, were quick to welcome Obama as one of their own. In their responses, the two seemed to be implying that a Republican president is unnecessary if Obama is selling their policy.

Kagan called the Obama speech "Kennedy-esque" for recognizing America's special role in the world and extolling American exceptionalism and defense of universal values. Even on multilateralism, according to Kagan, such multilateral efforts could only be galvanized by American leadership and Obama appeared to realize this in his address.

Kristol welcomed the "you've come a long way, baby" Obama address as an "unapologetic, freedom-agenda-embracing" speech. 

Others were happy that Obama had to reverse some of his previously enunciated positions,such as those in his 2008 campaign, when he stated in his campaign book "The Audacity of Hope" that the US needed "a well articulated strategy that the public supports and the world understands". Why was invading Iraq correct and not North Korea or Burma, then-candidate Obama asked. Now he is asked  "why Libya and not Syria" by Republican presidential aspirant Tim Pawlenty.

Like any good politician, Obama strove for the center ground and portrayed his actions as the judicious avoidance of the two extremes.

One is the extreme that questions why America should intervene at all. since "there are many places in the world where innocent civilians face brutal violence."

The other extreme tends to ignore American limitations and the need to "measure our interests against the need for action."

The latter view was on display in the regime change that the US attempted in Iraq, but, said Obama, "regime change there took 8 years, thousands of American and Iraqi lives and nearly $1 trillion. That is not something we can afford to repeat in Libya." While his speech pleased the neoconservatives, Obama had to throw in that line to convince his constituency that he had not morphed into George Bush.

What Obama is trying to build is a doctrine that is not doctrinaire, one that allows America diplomatic flexibility. An immediate threat to the United States would be countered immediately, even by unilateral American action. "I've made it clear that I will never hesitate to use our military swiftly, decisively and unilaterally when necessary to defend our people, our homeland, our allies and core interests," he said. 

Issues that do not fall under that heading will require favorable conditions, such as a coalition of forces that would spare the United States the necessity of carrying costs alone. Presumably it would also have to have international legitimacy such as UN sanction.

It would be unfair to Obama to swoop down on inconsistencies. Any policy approach is going to be riddled by inconsistency. It was Ralph Waldo Emerson, who characterized consistency as the hobgoblin of little minds. There will always be a trade-off between flexibility and clarity.

However, there was also sleight-of-hand in the address, in the emphasis that NATO was going to assume leadership of the operation, as if by this name change the United States  would be spared the lion's share of the operation's burden.

It is very well for Obama to criticize how the regime change came about in Iraq and to avoid an extended commitment. However, he has said from the outset that Qaddafi must go. If Qadaffi remains in power or if a stalemate develops in Libya, the tyrant will  be transformed into the hero who stood up to America, as Nasser was after Suez.

Obama's UN Ambassador talks of arming the insurgents. Therefore it is clear that Obama is going for regime change in Libya. If Qaddafi is ejected, who is going to run Libya? Who is going to make sure it does not turn into a failed state on the Mediterranean within a short distance of Italy? Iraq has shown that toppling a regime is the easy part while building a replacement is the harder task.

The United States has the power and the will to defend its national interests. But what does that term mean?  Responding to a missile attack on Chicago is an obvious decision, but what happens if China decides to invade Taiwan?

If the United States, for example, decides that it cannot act in Iran or Syria in the same way that it acted in Libya, will it at least brand these countries as part of an axis of evil and seek their isolation? Or will it try to engage them?

Will it try to beautify the situation as Hillary Clinton did when she labeled Bashar Assad a reformer?

These are only some of the questions that arise. Some of them have no answer, even from the occupant of 1600 Pennsylvania Avenue.