How did Israel manage to keep the opening strike secret and surprise the Iranians?

Take note of what was required from Israeli cabinet ministers who approved the attack during the night. Around 8 p.m. on Thursday, a meeting was held during which a vote on the attack against Iran took place.
First, they were required to sign a confidentiality agreement, meaning they were absolutely forbidden from leaking anything. Second, their phones were taken, the ministers were brought into a closed compound, and were not allowed to leave until explosions began to be heard in Iran. For many hours, they sat there without being allowed to meet anyone from outside, to ensure this information would not leak or get out.
Israel operated with a very high level of sophistication, even deploying diplomats to make specific statements, like the tweet by U.S. President Donald Trump around midnight in which he wrote that the U.S. would do everything possible to resolve the conflict with Iran through diplomatic means.
They even scheduled entirely fictitious security meetings for the following week, to mislead the Iranians into thinking that Israel was still in discussion and did not intend to carry out an attack soon. A great deal of cunning was required to enable the surprise opening strike that was executed against the Iranians.

Michael Shemesh is a political correspondent for KAN 11 news.