Answer this question with respect to the Cold War: Can what you do not do be as powerful as what you do?
The answer to this question is a clear yes, and the Cold War provides a number of good examples. One particularly prominent example is the response of the Kennedy Administration to the Cuban Missile Crisis in 1962. Faced with a range of options, John F. Kennedy opted not to launch an invasion of the island, or, more plausibly, to send planes in to destroy the missile sites. Many of his advisors disagreed with this decision, but we know now that many of the missile sites on the island were operational, and that the USSR and Cuba had tactical nuclear missiles that they were prepared to use against an invading force. A heavy-handed military response may well have sparked World War III, and almost certainly would have led to a catastrophic loss of life. Kennedy (and, it should be noted, Khrushchev, who was careful in dealing with the issue of a US quarantine of the island) by choosing not to attack immediately, made a diplomatic solution possible.