The acquisition of California brought up a new problem of quick transit between Atlantic and Pacific, and a canal was planned across Central America.  Here Britain and America acted together, at first in amity, though the convention signed in 1850 later developed discord as to the British claim of a protectorate over the Atlantic end of the proposed canal at San Juan del Nicaragua.  But Britain was again at war in Europe in the middle ’fifties, and America was deep in quarrel over slavery at home.  On both sides in spite of much diplomatic intrigue and of manifestations of national pride there was governmental desire to avoid difficulties.  At the end of the ten-year period Britain ceded to Nicaragua her protectorate in the canal zone, and all causes of friction, so reported President Buchanan to Congress in 1860, were happily removed.  Britain definitely altered her policy of opposition to the growth of American power.

In 1860, then, the causes of governmental antagonisms were seemingly all at an end.  Impressment was not used after 1814.  The differing theories of the two Governments on British expatriation still remained, but Britain attempted no practical application of her view.  The right of search in time of peace controversy, first eased by the plan of joint cruising, had been definitely settled by the British renunciation of 1858.  Opposition to American territorial advance but briefly manifested by Britain, had ended with the annexation of Texas, and the fever of expansion had waned in America.  Minor disputes in Central America, related to the proposed canal, were amicably adjusted.

But differences between nations, varying view-points of peoples, frequently have deeper currents than the more obvious frictions in governmental act or policy, nor can governments themselves fail to react to such less evident causes.  It is necessary to review the commercial relations of the two nations—­later to examine their political ideals.

In 1783 America won her independence in government from a colonial status.  But commercially she remained a British colony—­yet with a difference.  She had formed a part of the British colonial system.  All her normal trade was with the mother country or with other British colonies.  Now her privileges in such trade were at an end, and she must seek as a favour that which had formerly been hers as a member of the British Empire.  The direct trade between England and America was easily and quickly resumed, for the commercial classes of both nations desired it and profited by it.  But the British colonial system prohibited trade between a foreign state and British colonies and there was one channel of trade, to and from the British West Indies, long very profitable to both sides, during colonial times, but now legally hampered by American independence.  The New England States had lumber, fish, and farm products desired by the West Indian planters, and these in turn offered needed sugar, molasses, and rum.  Both parties desired to restore the trade, and in spite of the legal restrictions of the colonial system, the trade was in fact resumed in part and either permitted or winked at by the British Government, but never to the advantageous exchange of former times.