That's complicated because each of these countries, as well as many others, export terror this way or another, directly or indirectly. Some do it even without their knowledge, like many western countries that donate money for humanitarian aid without knowing where it really goes to.
Israel, for example, has a semi-private military industry (which was formerly state owned). Now when it's in private hands, its main interest is profit and in the past it sold technologies to China, which later sold it to North Korea, Iran, and whoever would pay. In other words, Israeli businessmen shot themselves in the leg when they decided to do business with China. Now it sold models and plans of Israeli planes to Iran, which now knows what kind of systems Israel operates.
If you ask Russian soldiers who been to Chechnya, they will tell you the Islamic resistance troops they met there are often not Chechen at all but rather mixed nationalities, from all corners of the world (Afghan, Egyptian, Iranian, Pakistani, even Nigerian) and trained in various locations, from Afghanistan, to Syria, to Iran, to Pakistan and so on.
Recently, several training grounds like that were discovered in England.
You know what can we all find in common with Nations exporting terror? Many of them are receiving Foreign Aid money from the USA. Yes, that's the poor suckers I was talking about who don't even know what their tax money is funding.
I wanna put up satire puppet-show "Punch n' Judi" style, only with Udo Vogit and Michel Friedman. I figure Friedman will be Judi...