Another topic respecting war， which it is of importance to consider in this place， relates to the mode of conducting it. Upon this article， our judgement will be greatly facilitated by a recollection of the principles already established， first， that no war is justifiable but a war purely defensive； and secondly， that a war already begun is liable to change its character in this respect， the moment the object pursued in it becomes in any degree varied. From these principles it follows as a direct corollary that it is never allowable to make an expedition into the provinces of the enemy， unless for the purpose of assisting its oppressed inhabitants.
It is scarcely necessary to add that all false casuistry respecting the application of this exception would be particularly odious； and that it is better undisguisedly to avow the corrupt principles of policy by which we conduct ourselves than hypocritically to claim the praise of better principles， which we fail not to wrest to the justification of whatever we desire. The case of relieving the inhabitants of our enemy's territory， and their desire of obtaining relief， ought to be unequivocal； we shall be in great danger of misapprehension on the subject when the question comes under the form of immediate benefit to ourselves； and， above all， we must recollect that human blood is not to be shed upon a precarious experiment.
The occasional advantages of war that might be gained by offensive operations might be abundantly compensated by the character of magnanimous forbearance that a rigid adherence to defence would exhibit， and the effects that character would produce， both upon foreign nations， and upon our own people. Great unanimity at home can scarcely fail to be the effect of a direct and clear conformity to political justice. The enemy who penetrates into our country， wherever he meets a man will meet a foe. Every obstacle will oppose itself to his progress， while everything will be friendly and assisting to our own forces. He will scarcely be able to procure the slightest intelligence， or understand in any case his relative situation. The principles of defensive war are so simple as to procure an almost infallible success. Fortifications are a very equivocal species of protection， and will perhaps oftener be of advantage to the enemy， by being first taken， and then converted into magazines for his armies. A moving force on the contrary， if it only hovered about his march， and avoided general action， would always preserve the real superiority. The great engine of military success or miscarriage is the article of provisions； and the further the enemy advanced into our country， the more easy would it be to cut off his supply； at the same time that， so long as we avoided general action， any decisive success on his part would be impossible. These principles， if rigidly practiced， would soon be so well understood that the entering in a hostile manner the country of a neighbouring nation would come to be regarded as the infallible destruction of the invading army. Perhaps no people were ever conquered at their own doors， unless they were first betrayed， either by divisions among themselves， or by the abject degeneracy of their character. The more we come to understand of the nature of justice， the more it will show itself to be stronger than a host of foes. Men whose bosoms are truly pervaded with this principle cannot perhaps be other than invincible. Among the various examples of excellence， in almost every department， that ancient Greece has bequeathed us， the most conspicuous is her resistance with a handful of men against three millions of invaders.
One branch of the art of war， as well as of every other human art， has hitherto consisted in deceit. If the principles of this work be built upon a sufficiently solid basis， the practice of deceit ought， in almost all instances， to be condemned， whether it proceed from false tenderness to our friends， or from a desire to hasten the downfall of injustice. Vice is neither the most allowable nor effectual weapon with which to contend against vice. Deceit is certainly not less deceit， whether the falsehood be formed into words， or be conveyed through the medium of fictitious appearances.
A virtuous and upright nation would be scarcely more willing to mislead the enemy， by false intelligence， or treacherous ambuscade， than by the breach of their engagements， or by feigned demonstrations of friendship.
There seems to be no essential difference between throwing open our arms to embrace them and advancing towards them with neutral colours， or covering ourselves with a defile or a wood. By the practice of surprise and deceit， we shall oftenest cut off their straggling parties， and shed most blood.
By an open display of our force， we shall prevent detachments from being made， and intercept the possibility of supply， without unnecessary bloodshed；第一章nd there seems no reason to believe that our ultimate success will be less secure. Why should war be made the science of disingenuousness and mystery， when the plain dictates of good sense would answer all its legitimate purposes？ The first principle of defence is firmness and vigilance. The second perhaps， which is not less immediately connected with the end to be attained， is frankness， and the open disclosure of our purpose， even to our enemies. What astonishment， admiration and terror might this conduct excite in those with whom we had to contend？ What confidence and magnanimity would accompany it in our own bosoms？ Why should not war， as a step towards its complete abolition， be brought to such perfection as that the purposes of the enemy might be baffled without firing a musket， or drawing a sword？