It will not arise where the separate States are so powerful as to be able to rely, for protection against foreign encroachment, on their individual strength. “If they are” said J. S .Mill, “they will be apt to think that they sacrifice in their own liberty of action; and consequently, whenever the policy of the (con) federation, in things reserved to its cognizance, is different from that which any one of its members would separately pursue, the internal and sectional breach will, through absence of sufficient anxiety to preserve the union, be in danger of going so far as to dissolve it