Why Must Obama Use a Marxist Catch Phrase To Attack His Critics?

Earlier today the Barack Obama lashed out at President Bush over comments he made to the Knesset in Jerusalem on appeasing terrorists and thug regimes.
Obviously, Senator Obama thought he was included in this "appeaser" category:

"George Bush knows that I have never supported engagement with terrorists, and the president's extraordinary politicization of foreign policy and the politics of fear do nothing to secure the American people or our stalwart ally Israel."

This is not the first time that Barack Obama lashed out, not at the terrorists, but at those who question his security positions...
He lashed out on April 25, 2007--

The top two Democratic presidential contenders rebuked Republican rival Rudy Giuliani on Wednesday for suggesting the United States could face another major terrorist attack if a Democrat is elected in 2008.

"Rudy Giuliani today has taken the politics of fear to a new low and I believe Americans are ready to reject those kind of politics,"

And, on December 28, 2007--

Mr Obama gave the most powerful speech of his campaign, urging the crowd to reject the Clintons’ politics of cynicism and fear in what his campaign calls his “closing argument”.

On April 21, 2008--

The 30-second broadcast does not mention Obama by name, but the Illinois senator’s spokesman Bill Burton fired off a robust response and brought up Clinton’s vote in 2002 to authorize the Iraq war, which his boss opposed.
“It’s ironic that she would borrow the president’s tactics in her own campaign and invoke bin Laden to score political points,” Burton said.
“We already have a president who plays the politics of fear, and we don’t need another,” he said.

On March 30, 2008--

"We need to break the politics of fear that uses 9/11 to scare up votes."

And, that is just the short list.

But, where did Obama get this catch phrase?
The phrase "politics of fear" is actually an old Marxist phrase used during the Cold War.
The New York Sun reported this back in January:

The phrase, "politics of fear," reemerged from the dustbin of anti-anti-communism on far left Web sites like Alternet in late 2002. In the Cold War, it was employed to deride public school air raid drills, the House's un-American Activities Committee, and Ronald Reagan's anti-red campaigns. Since the end of the Cold War, the phrase has been resurrected by politicians and pundits alike to say the electorate ought to fear the people trying to scare us, not these terrorists and tyrants they keep going on about.

Surprised?... Didn't think so.