NEW YORK, Nov 9 (Reuters) – Lazard's new (LAZ.N) Chief Executive Officer Peter Orszag said escalating geopolitical tensions in China, Ukraine and the Middle East have become a top focus for clients. "It's pretty simple – you can't make a big business decision today without a geopolitical perspective," Orszag said in an interview at the Reuters NEXT conference in New York. "There is no such thing as an isolated business decision today, you can't just look at the Excel spreadsheet and say yes or no, you have to have the context," said Orszag who took the helm at the independent…