Do you support a wall on the Polish East border?
Don`t doing that.
It would be mistake. Mistake that could annul Poland first from within.
Even if you exclude moral dinesions of it (it would be wall that cut trhu the Slavic civlization) there is bigger problem at hand. You build wall you have to defend the wall and key enemy of Poland isn`t on the East but on the West. So wall would be victory of that enemy from West. Geographical West. It would mean that Poland doing service to that enemy in its own home that wouldn`t even exist if that enemy from West was asked.
What countries need is this >
Automatic robotic machine gun turrets that have its limited `Killing zone` and range along the borders in areas outside of offical border crossings. Sensors whould guaranty constant identification of `hostile or illegal` human targets.
You want to cross border illegaly, you doing that on your own responsibility. Just simple as that.