Begin stood very strongly in the face of immense pressure. He was unapologetic about his Jewishness and the Land of Israel. Here's one example:
In July 1977, when Zbigniew Brzezinski presented Begin with a draft statement regarding the just-concluded U.S.-Israel meeting. Begin told Brzezinski that the draft was acceptable — “except for two sentences.” Brzezinski asked what they were:
“Please delete ‘The United States affirms Israel’s inherent right to exist.’”
“Why so?”
“Because the United States’ affirmation of Israel’s right to exist is not a favor, nor is it a negotiable concession. I shall not negotiate my existence with anybody, and I need nobody’s affirmation of it.”
Brzezinski’s expression was one of surprise. “But to the best of my knowledge every Israeli prime minister has asked for such a pledge.”
“I sincerely appreciate the president’s sentiment,” said Begin, “but our Hebrew Bible made that pledge and established our right over our land millennia ago. Never, throughout the centuries, did we ever abandon or forfeit that right. Therefore, it would be incompatible with my responsibilities as prime minister of Israel were I not to ask you to erase this sentence.” And then, without pause, “Please delete, too, the language regarding the commitment to Israel’s survival.”
“And in what sense do you find that objectionable?”
“In the sense that we, the Jewish people alone, are responsible for our country’s survival, no one else.”