Months of violent protests last year wreaked havoc on Hong Kong, and to prevent the violence from flaring up again, a draft decision on a national security law for the Special Administrative Region was submitted to China's national legislature for deliberation. But what's the background story, the legal basis, and the key to making the "One Country, Two Systems" principle work? Do the media stories cover all these nuances? In this week's Headline Buster, we dissect three examples and fill in the missing pieces of the puzzle.