From the preceding statements it will be observed that carriers have another important commercial function beside that of equalizing industrial conditions.[123] They also act in a protective or insurance capacity to the merchant or manufacturer. The policy of "keeping everyone in business" implies not only variety but variability of conditions. Capital is proverbially timid. It will not venture into a new and uncertain enterprise unless either profits are immediate and high or, if moderate, likely to endure. In any event some guarantee of permanence is required. This guarantee the carrier is often able to offer. It may assume the obligation of protecting its clients; that is, of saving them harmless against the intrusion or irruption of hurtful competition. It thus exercises in a certain sense the function of an insurance company, but with this important difference: that while it has the strongest interest in protecting its established industries against ruinous competition from abroad, it may desire to share in some degree in their development and prosperity by way of reward. In this latter sense the relation of the carrier to its clients partakes of a profit-sharing arrangement. One of the broadest issues between American railways and the public at the present time is precisely this: whether the carriers are to share in business profits; or merely, in addition to furnishing transportation, are to collect a fixed fee for a service in the nature of industrial insurance. That it lies in their way to furnish such protection under modern economic practice is an indisputable fact.