6 weeks 1 day 21 hours ago Obama visits holocaust memorial in Israel Play video

(NECN/ABC) - Laying a white floral wreath at the Yad Vashem holocaust memorial in Israel- Barack Obama recognized the 6 million Jews who died during the holocaust.

The visit was part of a quick, thirty hour trip to Israel and the Palestinian territories. Obama has promised to work towards an Israeli Palestinian peace deal if he's elected - but there is another looming threat to Israel - Iran.

John McCain has said the only thing worse than war with Iran- is a nuclear Iran... And Obama acknowledged the problems a nuclear Iran would pose during an interview with ABC's Charles Gibson.

Obama: If Iran gets a nuclear weapon, it triggers a potential arms race, a nuclear arms race in the middle east. that is not only life-threatening to Israel, but it is a profound game-changing shift when it comes to our national security. we have to do everything we can to prevent it.

On the campaign trail in Pennsylvania- McCain turned his attention to domestic issues- arguing that Obama is refusing to negotiate on energy policy.

MCCAIN WRIGHT CLIP " He has said no to every proposal that would help this nation emerge from this terrible problem of gas prices. He's against nuclear power. He's against offshore-drilling. He's against a gas tax holiday so if you're not part of the solution you're part of the problem."

McCain also hammered Obama on his Iraq policy- saying his idea to withdraw troops over a 16 month period could lead to a return of violent insurgent