Verified answer

They wouldn't be classified as a terrorist group if they did. Tanks and aircraft leave a signature, are easy to spot, and do not blend into the civilian population. They also require facilities. When terrorists have those things, to include facilities, they are quickly identified and destroyed. They often cost more then it is worth to them. Also, to be useful, they would need enough to be a force. 1 helicopter or 1 tank by itself is not really useful in most situations when you look big picture.

They may take over one of these items, but will use it for a trophy to rally people then use it in combat. Terrorist type groups will get more benefit from letting a mob of people dance around on a captured vehicle then trying to drive it around.

They may have tactical use of some lighter vehicles, such as trucks or captured wheeled vehicles. But your not going to be able to drive up to a base with a captured tank since a tougher inventory is kept on them then on trucks. Everybody on a base knows when a tank rolls out and when it doesn't come back. However not as many people keep count on how many truck go out because so many go out.

Oh yes, they do. Tanks, helicopters, and missiles are all available on the black market, aisle six on sale. The thing is, they chose not to have it because one, it takes a lot of energy to maintain and two, it's impossible for those equipments to compete with that of the United States. So they rely on guerrilla warfare which is more easier and more demoralizing. Car bombs, skilled assassinations, random murder, hijacking basically have more effect on the enemy than any tanks or helo. The purpose of terrorism is to rock the foundation of the existing government, lose faith in the current administration.

Don't believe that to be correct

Yes. The largest group that has access to such things would be the Tzvah Haganah L'Yisrael aka Israel Defense Forces.

if they did thay wouldent have it for long that would be the first thing we would drop a bomb on