ome to certain well-defined military
conclusions. The plans of General Cadorna had involved three separate
campaigns--one in the Trentino, the other in the Carso, and a
subsidiary campaign in the Carnic Alps to the north, along the main
watershed of the mountains. A general offensive in the Trentino had
been tested and found well-nigh impossible. Trentino is indeed a
military paradox--a sharp salient jutting into Italy, which is strong
by reason of its being a salient. This is because it is inclosed on
eight sides by great walls, the batteries of the main Alpine chain. A
salient is weak as a strategical situation in proportion to the
possibility of crushing in its sides and threatening the lines of
retreat of the forces occupying the point. Where the sides cannot be
successfully attacked, it becomes a position of strength and remains a
constant threat. This was the situation in the Trentino. The main
Alpine chain is not impassable. It is indeed conceivable, under
exceedingly favorable circumstances, that one or more of the passes on
the east or west side might be taken and an advance down the valleys
to the Adige turn the positions of the defenders. But ordinary
foresight on the part of the defense would make this impossible. The
valley of the Adige is the only avenue through the Trentino, and this
avenue, which is at best only a narrow road, was heavily guarded by
the strong fortress of Trent. Moreover, there could be but little
result accruing to Italy if the Trentino were forced. The Adige leads
only to the main chain of the Alps, and farther on, across the
mountains by the easiest of Alpine highways, is the Brenner Pass.
Modern defensive power is so great that its development to the point
where this highway would be impregnable, except against overwhelmingly
superior numbers, would be a matter of great simplicity. Along the
northern frontier, in the Carnic Alps, the situation is similar. There
is only one pass across these mountains, and this the Austrians could
block with the same facility and certainty with which they could block
the Brenner Pass.

On the other hand the presumption that the Isonzo sector had a degree
of vulnerability was found correct, and along the Isonzo line the real
Italian offensive from the beginning continued to be directed. The
Isonzo is roughly about three miles into Austria, beyond the political
boundary. But it is the true military boundary between Italy and
Austria, and it was always