The suggestion is that Osama's death will prompt a more rapid scaling back of military operations by America, which means less spending on their military budget... and if that were to happen, the American budget, and its economy, will be in better shape sooner (that speculation by investors is what is said to be strengthening the US$ in the last few days). Give it a week, and we'll see if the speculation dies down or is justified (by way of further announcements on their operations against Al Quaeda and Afghanistan).