According to the Displacement Hypothesis developed by Peacock and Wiseman (1961), there is a rapid increase in public expenditures during periods of economic and social crisis. When the crisis disappears, public expenditures return to their previous level. The aim of this study is to test the validity of the Displacement Hypothesis for selected MENA countries (Egypt, Iran, Israel, Tunisia). The data set of the study is determined as the share of countries' military expenditures in GDP. Fourier Unit Root Tests that allow for soft breaks are used as the methodology in the study. The data range covers the years 1962-2022. All data are obtained from the World Bank database. The fact that the series is found to be stationary indicates the validity of the Displacement Hypothesis. The presence of a unit root in in the military expenditure/GDP series of any country indicates that the Displacement Hypothesis is not valid. In other words, the fact that military expenditure/GDP values tend to return to the average over time means that the Displacement Hypothesis is valid. According to the results obtained from the study, the Displacement Hypothesis is valid for Egypt, Iran and Tunisia. For Israel, the Displacement Hypothesis is not valid.