Athens   Amid the economic and social upheaval of Greece’s beleaguered capital city, where demonstrators have been protesting government-imposed austerity measures, forty activists from across the United States began training this week to nonviolently confront the Israeli military blockade of Gaza. The Americans are part of a flotilla of ten ships—from France, Ireland, Canada, Norway, Greece, Sweden and other countries—planning to set out for Gaza’s main seaport in the next week to relieve the siege.

With an age gap of sixty years between the youngest and oldest passenger, the diverse group of Americans have taken over a hotel in a trendy Athens neighborhood for days of nonviolence training and preparation.

Israel has stated that it will enforce its naval blockade by any political, military and economic measures at its disposal. This week it submitted an urgent request to UN Secretary General Ban Ki-moon asking for international cooperation in stopping the flotilla. Ban embraced the Israeli government’s position, arguing in a public statement that aid should be delivered to Gaza only through “legitimate crossings and established channels,” all of which are controlled by Israel. Ban added that the flotilla is not helpful in assisting the economy of Gaza and encouraged organizers to cancel their voyage.

According to flotilla organizers, who are reticent about their sources, Israel has been meeting with Greek officials in a bid to persuade them to block Gaza-bound ships leaving from their ports. Israel, organizers say, could use economic incentives at a delicate time of EU-imposed austerity to put pressure on Athens. In recent years Greece and Israel have expanded trade ties, have carried out joint air force exercises and have begun discussions on a joint pipeline project that would exploit vast new Israeli natural gas fields in the eastern Mediterranean.

“Israel has pulled out the stops in trying to get the flotilla to stop before it begins by threatening the Greek economy,“ said Ann Wright, a retired State Department official and former Army colonel who is the main organizer of the US boat to Gaza. Sitting in the lobby of the noisy Athens hotel, she added, “Greece is caught in the middle. There is tremendous public support for the flotilla, but the government is getting pounded by the Israelis.” Not naming her sources, Wright, visibly exhausted from a year of organizing for the flotilla, contended that “Israel is going to try to sink the Greek economy if they allow the flotilla to sail from Greek ports.”

In response to the growing pressure, the Greek foreign ministry released a public statement on June 22 regarding its own citizens sailing with the flotilla. According to the statement, the ministry “urges Greek citizens as well as Greek-registered vessels not to participate in the new flotilla headed for the Gaza port.”

“Everything is explained in great detail,” foreign ministry spokesman Georgy Delavekouras told me over the phone from his office in Athens, referring to the statement. However, the statement is vague and does not say whether Greece will stop Gaza-bound ships registered in other countries.

Confirming that meetings between Greece and Israel have taken place recently over “many issues, including the flotilla,” Delavekouras said the Israeli government has not applied economic pressure. When pressed on the nature of the Israeli-Greek discussions, he simply referred to the statement.

Israel is doing everything possible to avoid a repeat of last year’s flotilla debacle, when Israeli commandos stormed the largest of six boats, the Turkish-flagged Mavi Marmara, and killed nine passengers, including one Turkish-American citizen, as they seized control of the ship.

Last week Turkish organizers pulled out of this year’s flotilla, citing “technical problems.” Flotilla organizers in Greece believe Israeli diplomatic and military pressure was the primary motivation for the cancellation. Citing internal discussions with their Turkish counterparts, flotilla organizers believe the Turkish government intervened directly to block the Mavi Marmara after negotiations with Israel.

Writing in the English-language Turkish daily Hurriyet on Monday, columnist Semih Idiz argued that the Turkish government probably did intervene to stop the Mavi Marmara’s participation, even though both the government and the IHH, the Islamic charity sponsoring the boat, have denied it. Citing growing tensions on the Turkey-Syria border, Idiz argued that Ankara is simply not prepared for a fresh crisis with Israel, especially since the two countries have been working to mend ties since last year’s disaster. While speculative, his analysis is echoed by Israeli Prime Minister Benjamin Netanyahu’s recent calls for the need to repair Turkish-Israeli relations.

Regardless of the pressure, the American boat, dubbed the Audacity of Hope after the title of President Obama’s autobiography, is determined to sail from an undisclosed Greek port with its passengers, among them Pulitzer Prize–winning author Alice Walker and 87-year-old Holocaust survivor Hedy Epstein. Unlike other ships in the flotilla, the US boat will be carrying only personal letters from American citizens to Gaza Palestinians. Boats from Ireland, Canada, France and Greece will be carrying goods ranging from medical supplies to sewage repair systems. The American boat, and perhaps some of the others, will be outfitted with advanced satellite communications systems that—if Israel does not jam them—will allow passengers to use social media platforms such as Twitter directly from the boat.

Despite the presence of former State Department official Wright and former CIA officer Ray McGovern, the US government has largely bowed to Israeli pressure over the flotilla. Issuing a rare maritime warning this week to American vessels traveling near Gaza, Washington has effectively distanced itself from offering protection to its citizens if they are attacked by Israel on the open sea. The import of the message is, “We warned you not to go.”

On the top deck of a recently refurbished ferryboat, the enormity of the upcoming voyage was visible on many of the US passengers’ faces. They busied themselves with tasking who would be cooking, maintaining lookout and helping with the upkeep of the ship while on the sea, but the nervous excitement of the pending journey was difficult for most to conceal.

“If the Israeli public could look around and see these wonderful people going on this boat, I think they would take pause and wonder what it is that Israel is doing in Gaza that has caused these types of people to risk their lives in challenging it,” Code Pink and Global Exchange founder Medea Benjamin noted on a bus ride through Athens. “I’m scared about going on this boat because I know the Israelis might attack us and my American passport is not going to protect me, but at the same time I feel incredibly privileged.”

During an intense day of nonviolence training in a dank underground karate studio in Athens, US passengers watched graphic videos of the Israeli raid last year on the Mavi Marmara. Anticipating how the Israeli navy will attempt to take over the Audacity of Hope, the organizers rehearsed violent scenarios in which Israeli soldiers beat passengers as they boarded the ship.

“We are making sure that the passengers will be able to stay calm in whatever scenario they face as they approach Gaza,” one of the organizers remarked in a break from the training. She added that the most important objective is that passengers remain nonviolent even if the Israelis provoke them with attack dogs, tear gas or—in the worst case—live ammunition shot from helicopters hovering above the ship.

With the participation of unarmed, older civilians, many of whom are Jewish, the Gaza flotilla may have found Israel’s Achilles heel, a way to neutralize its military prowess. The internationalization of nonviolent protest, also seen in the years-long demonstrations against Israel’s separation barrier in the West Bank, is drawing worldwide attention to Israel’s occupation and control over Palestinian life. So far, Israel has shown that it is ill equipped to stop it.