"The independence of nations is spoken of sometimes as if it rested on another foundation—as if each separate race or community had a divine titledeed to dispose of its own fortunes, and develop its tendencies in such direction as seems good to itself. But the assumption breaks down before the enquiry, What constitutes a nation? And the right of a people to self-government consists and can consist in nothing but their power to defend themselves. No other definition is possible. Are geographical boundaries, is a distinct frontier, made the essential? Mountain chains, rivers, or seas form, no doubt, the normal dividing lines between nation and nation, because they are elements of strength, and material obstacles to invasion. But as the absence of a defined frontier cannot take away a right to liberty where there is strength to maintain it, a mountain barrier conveys no prerogative against a power which is powerful enough to overleap that barrier, nor the ocean against those whose larger skill and courage can convert the ocean into a highway."