Another sure sign that Barack Obama will be the Democratic nominee: President Bush has already started taking shots at him.

Almost clearly referring to Obama, who said last July that he supported direct and unconditional talks with leaders of Iran, North Korea and other countries, Bush said this today in a speech in Israel:

“Some seem to believe that we should negotiate with the terrorists and radicals, as if some ingenious argument will persuade them they have been wrong all along. We have heard this foolish delusion before. As Nazi tanks crossed into Poland in 1939, an American senator declared: ‘Lord, if I could only have talked to Hitler, all this might have been avoided.’ We have an obligation to call this what it is — the false comfort of appeasement, which has been repeatedly discredited by history.”

Obama’s campaign released a statement almost immediately, saying, “It is sad that President Bush would use a speech to the Knesset on the 60th anniversary of Israel’s independence to launch a false political attack.”

And, in response to Obama’s response, White House spokesperson Dana Perino made this biting comment: “I understand when you’re running for office you sometimes think the world revolves around you — that is not always true and it is not true in this case.”

TIME analyzes this exchange in a piece aptly titled “Behind the Bush-Obama Smackfest.” The obvious reason for Bush’s jab at Obama is that he is fighting on McCain’s behalf, but TIME says it goes further than that - and on both sides.

Bush is struggling to keep his presidency relevant, and injecting himself into the presidential campaign is a sure way to do that. At the same time, Obama is happy for any opportunity to tie Bush to Republican nominee-to-be John McCain’s side.

…

But the speed with which Obama responded to Bush’s Knesset comments says something about his eagerness to lock horns with the President and the use his campaign is going to make of him in coming months.

Obama may not like what the President said about him, but it does give him a chance to denounce him and - by association - John McCain. And McCain backed up the President today when asked about the situation:

“Yes, there have been appeasers in the past, and the president is exactly right, and one of them is Neville Chamberlain,” Mr. McCain told reporters on his campaign bus after a speech in Columbus, Ohio.

Asked if he thought Mr. Obama was an appeaser, Mr. McCain sidestepped the question and said, “I think that Barack Obama needs to explain why he wants to sit down and talk with a man who is the head of a government that is a state sponsor of terrorism, that is responsible for the killing of brave young Americans, that wants to wipe Israel off the map, who denies the Holocaust. That’s what I think Senator Obama ought to explain to the American people.”

That’s exactly what Obama wants - the sound bite of McCain saying, “And the president is exactly right.” McCain should be careful about how he associates himself with the unpopular President, as Obama will be looking to exploit their relationship every chance he gets. With record number of voters becoming more and more excited about Obama’s calls for change, the last thing they’ll want to hear about is a candidate who could bring more of the same from the Bush era.