Then again: it is often stated that Trafalgar saved England from
invasion. To refute this error it is merely needful to remind the
reader that all immediate fear of invasion was over, when, at the
close of August, Napoleon wheeled the Grand Army against Austria. Not
until the Continent was conquered could the landing in Kent become
practicable. That opportunity occurred two years later, after Tilsit;
then, in truth, the United Kingdom was free from panic because
Trafalgar had practically destroyed the French navy. For these
islands, then, the benefits of Trafalgar were prospective. But, for
the British Empire, they were immediate. Every French, Dutch, and
Spanish colony that now fell into our hands was in great measure the
fruit of Nelson's victory, which heralded the second and vaster stage
of imperial growth.

Finally, the decisive advantage which Britain now gained over Napoleon
at sea compelled him, if he would realize the world-wide schemes ever
closest to his heart, to adopt the method of warfare against us which
he had all along contemplated as an effective alternative. As far back
as February, 1798, he pointed out that there were three ways of
attacking and ruining England, either a direct invasion, or a French
control of North Germany which would ruin British commerce, or an
expedition to the Indies. After Trafalgar the first of these
alternatives was impossible, and the last receded for a time into the
background. The second now took the first place in his thoughts; he
could only bring England to his feet and gain a world-empire by
shutting out her goods from the whole of the Continent, and thus
condemning her to industrial strangulation. In a word, Trafalgar
necessitated the adoption of the Continental System, which was built
up by the events now to be described.