By Daniel Kline The major cruise lines walk a delicate line. They need to take the actual steps required to keep their passengers safe and they also need to be aware of how things look to the outside public. It’s a mix of practical covid policy balanced with covid theater. You have to do the right thing — and Royal Caribbean International (RCL) – Get Royal Caribbean Group Report, Carnival Cruise Lines (CCL) – Get Carnival Corporation Report, and Norwegian Cruise Lines (NCLH) – Get Norwegian Cruise Line Holdings Ltd. Report have been doing that with very meticulous protocols– but you also hav…