Used to be, partisanship in foreign policy was kept moderate, civil. The expression was, “Politics stops at the water’s edge.” Republicans and Democrats in Washington were happy to use the phrase; it implied they cared more about what’s good for America than politics. Those days are gone.

For the Republican leadership the goal since Jan. 20, 2009, has been to shoot down President Obama. Their foreign policy and domestic policy are the same: Whatever Obama wants, we oppose. Not every Republican every time, but close to it. Doesn’t matter if they shoot themselves in the process; that’s a risk they take. In their zero-sum game if Obama succeeds, they fail anyway.

This makes Republican politics highly predictable. What did Obama say or do? We’re against it. Before his speech to the nation on Libya March 28, all the early Republican 2012 presidential hopefuls were critical of Obama on Libya, a Huffington Post article reported.

The usual talking points are that he is incompetent, a socialist, not an American, etc., and that whatever Obama decides, the opposite policy is better.

Think health care reform and stimulus spending, and agreeing on a 2011 budget right now. There may be sincere political differences but there are virtually no attempts at compromise. The Republican goal is to defeat Obama, and hang the details.

Rudolph Giuliani, the 2008 presidential contender and coquette who campaigned only in Florida put it this way recently, speaking in Palm Beach: “My whole objective is to spend every bit of effort that I have in politics to make sure that we have Barack Obama as a one-term president.”

This overriding goal can lead to neat twists. When Obama resisted setting up a no-fly zone over Libya, some Republican leaders demanded one. He then put in an effective no-fly zone with UN backing and NATO and Arab involvement. It stopped a massacre – but also left the Republicans in a quandary. So they attacked him for either not doing enough or doing too much, or not explaining things well enough or for an explanation they didn’t like.

It’s true that some Democrats also have criticized Obama over Libya and that not every Republican has. In a way it pains me to single out Republicans for ridicule because the Democrats are almost equally deserving. But it is the Republicans who always keep the pressure on regardless of the issue or the outrageousness of their criticism. On Libya they struggle for new lines of attack, saying Obama hasn’t defined America’s goals, that implementing the no-fly zone costs too much money, that the U.S. should have struck sooner or that it wasn’t America’s business to interfere at all.

A Polonius buffoon of the week award could go to Newt Gingrich who on March 7 said the U.S. should set up a no-fly zone “this evening,” and on March 23, after Obama set one up, said, “I would not have intervened.” Asked about his change of position, Gingrich, well practiced at this sort of thing, explained that he hadn’t changed it.

Obama could have some fun with Gingrich. Just take a stand on an important issue, and wait a little. It’s like Act III, Scene Two in Hamlet, except in that instance, the prince gets the buffoon to agree, not disagree, with everything he says. Three different positions in 10 seconds:

Hamlet: Do you see that cloud, that’s almost in shape like a camel? 

Polonius: By the mass, and ‘t is like a camel, indeed. 

Hamlet: Methinks, it is like a weasel. 

Polonius: It is backed like a weasel. 

Hamlet: Or, like a whale? 

Polonius: Very like a whale.

How life imitates art.