Israel's intelligence services have been hailed as some of the world's best, but there are questions being raised now as Hamas launched massive terrorist attacks on the 50th anniversary of the Yom Kippur War.

An attack of Saturday's magnitude was likely years in the works, military analyst Patrick Fox told Politico.

"The last time Israel was blindsided this badly was the '73 war," Fox said. "The scope of this infiltration attack indicates a huge level of planning and preparation spanning months or years."

Also, the modern technology failed to provide advance notice of terrorist movements from Gaza into Israel and Israel's Iron Dome was overwhelmed by thousands of Hamas-fired rockets.

"This will shake Israel to its core," author Jonathan Schanzer told Politico. "The majority of the defenses that Israel has relied upon for the last 20 years appear to have been penetrated. So this obviously raises significant questions about Israeli military intelligence and Mossad."

The intelligence failure is akin to the breakdown before the 1973 Yom Kippur War, when the head of Israel's Military Intelligence Directorate wrote a memo to then-Prime Minister Golda Meir suggesting nothing was showing any imminent attack.

"I think they aren't about to attack; we have no proof," the 1973 memo read, according to Politico. "Technically, they are able to act. I assume that if they are about to attack, we will get better indications."

Former U.S. Ambassador to the U.N. Nikki Haley told NBC's "Meet the Press" on Sunday that "there will be a time and place to deal with whether it was an intelligence failure."

That echoed the statements of Secretary of State Antony Blinken to NBC on Sunday.

"There will be plenty of time to figure out whether the intelligence should have done something different to see this coming," Blinken said.

"This is an attack that I don't think anyone saw coming in the immediate.

"The Israelis will have plenty of time to look into that. All of us will have time to look into that."

Israeli reserve officer and former Israel Defense Forces spokesperson Jacob Dallal wrote for The Times of Israel that the military has been preparing for this attack but not in the way it ultimately came.

"This was the doomsday scenario we drilled in IDF military exercises over the last decade and a half: Terrorists infiltrate Israel en masse, take over entire Israeli towns, kill civilians, and take others hostage for later negotiations," Dallal wrote. "Incessant rocket fire, chaos, and fog-of-war on the Israeli side.

"This scenario played out exactly today — the only difference was the military scenario envisioned Hezbollah attacking from the north, not Hamas from Gaza. No one thought Hamas had such capacity, especially with the intelligence coverage by Israel's Shabak and IDF Intelligence."

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