Why was Switzerland safe and sound during World War I and World War II and did not participate in the war?

During World War II, Switzerland was in a state where all the people were soldiers. On the one hand, the government mobilized the army, on the other hand, it fought ideological wars among the people. Nowadays, many people think that the Swiss are really heartless: no matter whether the allied planes or the Axis planes fly over Swiss airspace, they will shoot you down without mercy. If Switzerland's air defense measures are the second in the world, no country dares to say that it is the first in the world. In 2006, Switzerland's air defense measures and the relative coverage rate of residents were 1 14%, while Finland and Sweden, with relatively high international coverage rates, were between 80% and 74% respectively. The Swiss government still spends a lot of money every year to maintain these seemingly unnecessary air defense measures. On the surface, Switzerland maintained a state of armed neutrality in World War II, but the situation is obviously much more severe than that in World War I. Now, the cohesion of various language areas is very strong, but Switzerland is counting the attacks from the Axis countries every minute. At the same time, as a small country with scarce resources and extremely dependent on import and export, the freedom of trade stipulated in The Hague Convention is a lifesaver for Switzerland. But at this point, Switzerland has completely destroyed its obligations: the domestic (official and private) arms supply of Switzerland to Germany and Italy is basically around 90%. At the same time, the transportation between Germany and Italy (via Switzerland) was closed, and the original strict inspection was completely unqualified ... not even inspection. Another violation of international conventions (in favor of allies) is the acquiescence of American news center in Bern. Switzerland struggled to survive between Germany and Italy, and the German unification advocated by Hitler almost included German-speaking Switzerland. Until February 1937, Hitler expressed respect for Switzerland's neutrality in a conversation with Edmund shulte Hess, one of the heads of the Swiss governing bodies.