The EU has actually been one of history's most successful projects for ensuring peace and prosperity in Europe. Looking at objective metrics like GDP growth, living standards, and decades of peace between former neighboring country adversaries over centuries, EU membership has broadly benefited its members. Poland itself has seen remarkable economic growth and development since joining in 2004. The single market, freedom of movement, and shared democratic values have created unprecedented opportunities for cooperation and development. While the EU isn't perfect, characterizing membership as 'national suicide' ignores the tremendous gains in stability, prosperity, and quality of life that integration has brought to member states. imho.