Sunak walks back into Number 10 Downing Street on Wednesday. Carl Court/Getty ImagesSunak’s speech was delayed by over 10 minutes. Speculation among those standing around on Downing Street was that he was waiting for the rain to clear.A let-up in the weather was shortly followed by the prime minister’s emergence from his official residence. The heavens almost immediately opened again, drenching Sunak.His back luck continued as protesters outside blasted the song “Things Can Only Get Better” by D-Ream, the anthem of Labour’s 1997 victorious election campaign. At this point it was…