“The Act of Navigation is not favourable to foreign commerce, or to the growth of that opulence which can arise from it.... As defence, however, is of much more importance than opulence, the Act of Navigation is, perhaps, the wisest of all the commercial regulations of England.” How completely the Navigation Act failed as a commercial measure appears from a number of passages in the _Wealth of Nations_ which together completely refute the fallacy, so generally adopted by English historians, that it ruined the Dutch, enriched England, and gave her a commercial and naval supremacy which she could not otherwise have achieved. Holland, he says, is richer than England; she gained the whole carrying trade of France during the late war; she still remains “the great emporium of European goods,” and so forth. All that Smith claims for the Act is that it helped to secure the country a sufficient supply of seamen for the navy in time of war. Further, as there are two cases (the necessity of defence and the propriety of countervailing an excise duty) “in which it will _generally_ be advantageous to lay some burden upon foreign for the encouragement of domestic industry, so,” continues Smith, “there are two others in which it may _sometimes_ be a matter of deliberation”: in the one, how far it is proper to continue the free importation of goods from a particular foreign country; in the other, how, and how far, free importation, after it has been interrupted for some time, should be restored. The first case of doubt is that of doing evil by retaliation in order that good, in the shape of freer trade, may come. Occasionally, he writes, it may be wise to retaliate, “when some nation restrains by high duties or prohibitions” the importations of our manufactures. After giving some examples of commercial retaliation, one of which ended in war, Adam Smith lays down the cautious rule that there may be good policy in retaliations of this kind, but only where there is a probability that retaliatory duties will procure the repeal of the high duties or prohibitions complained of. “The recovery of a great foreign market will generally more than compensate the transitory inconvenience of paying dearer during a short time for some sorts of things.” He leans strongly against the policy, partly because he is unwilling to trust “that insidious and crafty animal vulgarly called a statesman” to use such a weapon wisely; partly because you rarely benefit the sufferers and always injure other classes of your own citizens, than those whom you are trying to assist.