The worrisome blowback from Jihadist activities

Recently I was reading in the newspaper that Indonesia is worried that its citizens who have gone to Iraq and Syria to fight a jihad will come back battle hardened and may become a threat to peace in that nation. And it is not Indonesia alone but other countries like Britain, France and other European and Middle Eastern countries who have all supported this so called Jihad are worried that when their citizens come back, they will not be satisfied to see what is going on in their native countries and will try to supposedly "correct" them by waging Jihad at home. European countries are more worried since their citizens can travel visa free to several countries around the world and have the potential to create mayhem globally. There are no easy answers as Jihad was encouraged initially as the way to get rid of incumbent Syrian government and now that the genie is out of the bottle, several countries are trying to control this genie which has a mind of its own. I am not the one to tell these governments what to do since I know they are trying to prevent any catastrophe that may accompany if and when these Jihadist come back and try to practice their skills at home. But for a starter, their activities should be monitored right when they enter the country and keep them under surveillance to make sure that they don’t do anything stupid. How they meet their friends, relatives, their activities. I am sure they will be thinking along these lines. And now that the Syrian and Iraq war has inspired these people to be part of the Jihadist movement, the countries involved can only regret and take corrective measures to mitigate their mistake of supporting these conflicts in the first place.