If Adam Smith's second canon of taxation - that the tax which each individual is bound to pay ought to be certain, and not arbitrary - is applicable to any form of revenue, it should apply to the levy of customs duties. No other form of revenue has such great possibilities for influencing the industrial stability of a country. It is not so much a question of high duties or low duties, of revenue or protective tariff, as it is a question of being able to know what to expect.

A country can ill afford to make a political football of its tariff policies, yet this has been true in the United States practically from the beginning. Attempts to use nonpartisan tariff boards have been of no avail, and industry continues to fear a change in administration because of what may happen to the tariff. Where such uncertainty and instability exist, it is impossible to rely upon customs duties for any definite amount of revenue, and avenues must always be kept open through which deficiencies can be supplied.

Aside from the deranging of industry, then, an indefinite tariff policy also creates instability in the remainder of a fiscal system. The United States would do well to follow the example of some of the European countries in adopting and maintaining some definite policy, but the accomplishment of such an end seems surrounded with insurmountable difficulties. Because the tariff may have such important fiscal and industrial consequences, and because the United States is so far from any settled policy, it will be well to review somewhat in detail the tariff struggle as it has been waged, not only in the United States, but in a few other important countries.