From a financial perspective, Switzerland could definitely afford a larger military force (defence expenditure is around 0.6% of the GDP, as a comparison the NATO sets the guideline to 2% of the GDP [Note: Switzerland is not part of the NATO, but it is a useful comparison to neighboring countries]).
The question is solely political, how much money is Switzerland willing to spend for an army/airforce? And this question undoubtedly correlates with the current feeling of safety and threat of conflict.
The question is solely political, how much money is Switzerland willing to spend for an army/airforce? And this question undoubtedly correlates with the current feeling of safety and threat of conflict.