ISLAMABAD, May 27: Prime Minister Shehbaz Sharif on Monday declared a public holiday on May 28 to mark Youm-e-Takbeer, the day when Pakistan’s defence became impregnable after nuclear tests in the hills of Chagai, Balochistan in the year 1998. “Youm-e-Takbeer reminds how the entire Pakistani nation got united on that day to make the country’s defence invincible,” the prime minister …