“A professional does not act out of fervour, and is therefore more calm and less likely to make elementary errors. Not being idealistic he is not likely to have second thoughts at the last minute about who else might get hurt in the explosion, or whatever method, and being a professional he has calculated the risks to the last contingency. So his chances of success on schedule are surer than anyone else, but he will not even enter into operation until he has devised a plan that will enable him not only to complete the mission, but to escape unharmed.”