Israeli tank (Image: Tyom, Flickr)

The next question: if and when the Israeli army will start a ground offensive. "The World's" Quil Lawrence has the story.

Israel's Defense Minister Ehud Barak hinted today that Israel may expand its offensive: "We will do whatever it takes. We are ready to deepen and widen the operation in order to make sure that calm and tranquility will come back to the region."

There has been a steady buildup of Israeli land forces on the Gaza border. Tanks and artillery have been loaded onto trailers in the area, and thousands of reservists have been called up. So far the assault has been by air, and the Israeli air force it still has many targets in the Gaza Strip; but it’s widely assumed that some sort of land assault will follow.

Israel's prestige took a hit after its ground offensive in Lebanon in 2006. Israeli errors during that war gave a propaganda victory to another Islamic group: Hezbollah. Israel seems ready to launch another ground assault anyway -- that's because air power alone only goes so far.

A retired Israeli general says the real question is the goal of the operation: if it's a new ceasefire with Hamas, then air strikes might be enough; but if the goal is regime change in Gaza, Israel would need a much longer ground operation. That would involve higher risk, but would bring a higher reward.

PRI's "The World" is a one-hour, weekday radio news magazine offering a mix of news, features, interviews, and music from around the globe. "The World" is a co-production of the BBC World Service, PRI and WGBH Boston.

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