One great obstacle to the attainment of peace has undoubtedly arisen from the fact that Mexico has been so long held in subjection by one faction or military usurper after another, and such has been the condition of insecurity in which their successive governments have been placed that each has been deterred from making peace lest for this very cause a rival faction might expel it from power. Such was the fate of President Herrera's administration in 1845 for being disposed even to listen to the overtures of the United States to prevent the war, as is fully confirmed by an official correspondence which took place in the month of August last between him and his Government, a copy of which is herewith communicated. "For this cause alone the revolution which displaced him from power was set on foot" by General Paredes. Such may be the condition of insecurity of the present Government. There can be no doubt that the peaceable and well-disposed inhabitants of Mexico are convinced that it is the true interest of their country to conclude an honorable peace with the United States, but the apprehension of becoming the victims of some military faction or usurper may have prevented them from manifesting their feelings by any public act. The removal of any such apprehension would probably cause them to speak their sentiments freely and to adopt the measures necessary for the restoration of peace. With a people distracted and divided by contending factions and a Government subject to constant changes by successive revolutions, the continued successes of our arms may fail to secure a satisfactory peace. In such event it may become proper for our commanding generals in the field to give encouragement and assurances of protection to the friends of peace in Mexico in the establishment and maintenance of a free republican government of their own choice, able and willing to conclude a peace which would be just to them and secure to us the indemnity we demand. This may become the only mode of obtaining such a peace. Should such be the result, the war which Mexico has forced upon us would thus be converted into an enduring blessing to herself. After finding her torn and distracted by factions, and ruled by military usurpers, we should then leave her with a republican government in the enjoyment of real independence and domestic peace and prosperity, performing all her relative duties in the great family of nations and promoting her own happiness by wise laws and their faithful execution. If, after affording this encouragement and protection, and after all the persevering and sincere efforts we have made from the moment Mexico commenced the war, and prior to that time, to adjust our differences with her, we shall ultimately fail, then we shall have exhausted all honorable means in pursuit of peace, and must continue to occupy her country with our troops, taking the full measure of indemnity into our own hands, and must enforce the terms which our honor demands.