Harvard student Edan Razinovsky spent the weekend agonizing over whether he should book a ticket to Tel Aviv, as the Israeli army was calling up reservists from around the country, including Razinovsky's former unit, for a possible ground invasion into Gaza. 

Razinovsky, 26, moved to the U.S. from Israel when he was a toddler, and voluntarily joined the Israeli army two years ago for an 18-month stint. He remains officially registered as a reservist although as a student living abroad he isn’t obligated to return.

“When you are in the army, you train for conflict and you are prepared, but to actually go in is somewhat surreal,” said Razinovsky. “My former commander left me a voice mail the other day, saying the unit had been called up, and I have been going back and forth as to whether I should go or not.”

Razinovsky isn’t the only American caught up in the chaos. Americans both inside and outside of Israel have had their lives turned upside down in the last week and a half, from reservists who have felt the need to return to Israel, to brides-to-be forced to alter wedding day plans. There are no official figures as to how many American Jews live in Israel, but around 2,000 Americans move to Israel every year.

In southern Israel, support grows for action in Gaza

Razinovsky is now waiting to see how the conflict develops, and feels strongly that if his unit needs him, he will fly over, even if it means sacrificing the semester at Harvard.

Last week, the Israeli Defense Forces called up around 31,000 reservists with authorization to mobilize up to 75,000. Anecdotal reports suggest that quite a few Americans who have served in the Israeli army have now returned to serve in the current conflict.

Daily life thrown
Avi Schwartz, who grew up in Silver Spring, Md., is used to juggling the off-again, on-again clashes, having lived in Israel for more than 10 years. But as the operator of a tour company, the current conflict has forced him to think of ways to reposition his business.

“About half of a women’s group we were expecting to come this week cancelled,” said Schwartz, 34, as an air raid siren went off in Jerusalem. “There are still groups that want to come despite the violence, and now we are trying to find and organize tours for those that want to show their support for Israel.”

When Debbie Shuval moved to Israel from Manhattan in August to attend business school, she didn’t count on having to explain a war to her three young kids.

Clinton heads to Mideast on peace mission, Hamas remains defiant

“The kids see soldiers all the time, and my 3-year-old son often tells me that when he’s big he will also go to the war,” said Shuval. “The most difficult part of this flare up has been hearing about friends who have been called up. It makes the conflict feel so much more real; living in Jerusalem, the relative quiet can give you a false sense of calm.”

A wedding to remember
While Razinovsky was busy staying in contact with his commanders, Pnina Weiss spent the weekend reorganizing her wedding with just a few days to go. Rockets raining down from Gaza into the southern Israeli city of Ashkelon, where her wedding hall was located, had thrown her plans into disarray.

Fewer than four days later, and thanks to the generosity of friends, family and strangers, Weiss was able to rearrange her affair to take place in a hall 16 miles north of Tel Aviv, closer to her parents’ home in Raanana, where tree-lined streets are more reminiscent of Southern California than the Middle East.

She has yet to taste the food, and will be using centerpieces and decorations donated by a friend of a friend who is getting married the night before.

Despite the quick turnaround, Weiss’ wedding will be a smaller affair than originally planned. She had organized the wedding for Thanksgiving weekend to make it easy for friends and family in the U.S. to attend. At least 11 family members from America have cancelled with another 30 or so from Ashkelon also too nervous to travel on unprotected roads or to leave their kids alone.

“Putting off the wedding wasn’t an option,” said Weiss, who moved to Israel from Dallas when she was four. “I’m 34 and I’ve waited many years for this so what does the rest matter? I know on Thursday I’m getting married. It will definitely be a wedding that no one will forget.”

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President Barack Obama said Sunday that Israel has “every right” to defend itself against missile attacks by militants inside Gaza but warned that escalating the offensive with Israeli ground troops could undermine any hope of a peace process with the Palestinians.

"Let's understand what the precipitating event here that's causing the current crisis and that was an ever-escalating number of missiles that were landing not just in Israeli territory but in areas that are populated, and there's no country on Earth that would tolerate missiles raining down on its citizens from outside its borders,” Obama said at press conference in Thailand at the start of a three-nation tour in Asia.

“So we are fully supportive of Israel's right to defend itself from missiles landing on people's homes and workplaces and potentially killing civilians."

He added: "Israel has every right to expect that it does not have missiles fired into its territory. If that can be accomplished without a ramping up of military activity in Gaza, that's preferable. It's not just preferable for the people of Gaza. It's also preferable for Israelis, because if Israeli troops are in Gaza, they're much more at risk of incurring fatalities or being wounded."

Netanyahu: Israel prepared for ‘significant expansion’ of Gaza operation

Obama directed some of his comments to the heads of state of Egypt and Turkey, both countries that are supportive of the Palestinians. “Those who champion the cause of Palestinians should recognize that if we see a further escalation of the situation in Gaza than the likelihood of us getting back on any kind of peace track that leads to a two-state solution is going to be pushed off way into the future,” he said.

Obama's comments came as Israel's campaign against Hamas militants in Gaza blasted into its fifth day. Israel is at a crossroads of whether to launch a ground invasion or pursue Egyptian-led truce efforts, and Obama sought to clearly defend the U.S. ally's military rights while pushing for a halt in the violence.

Key players in the Israel-Gaza cross-border conflict

Israeli Prime Minister Benjamin Netanyahu declared Sunday that Israel was prepared to significantly expand its military operation in Gaza. Obama has been lobbying Netanyahu along with the leaders of Egypt and Turkey to try to halt the crisis -- including stopping rocket strikes on Israel.

Slideshow: Israel, Gaza violence escalates

Ammar Awad / Reuters

Two sides exchange deadly airstrikes, rocket attacks.

Launch slideshow

He said Israel was justly responding to "an ever escalating number of missiles that were landing not just in Israeli territory, but in areas that are populated. And there's no country on earth that would tolerate missiles raining down on its citizens from outside its borders."

Obama said Palestinians will have no chance to pursue their own state and a lasting peace with Israel as long as rockets are fired into Israel. He said he hoped for a clearer process over the next 48 hours -- showing how much the Mideast conflict had intruded on his diplomatic mission to Asia.

NBC News' Shawna Thomas and The Associated Press contributed to this story.

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