It depends on where you go.
The vast majority of Turkey is pretty safe. The border region (80 to 100kms) with Syria has a higher level of risk. There continue to be random attacks and small bombings in Istanbul, that's been going on for years. keep an eye on media reports and judge for yourself if it's getting worse in coming months.
Jordan - the same. Stay away from border regions. I imagine you'll go to Petra - and popular tourist attractions, although potential targets, usually also have increased security. No government wants their tourism industry to be affected.
Which brings us to Egypt - so many violent acts in popular tourism precincts means the confidence in the country as a destination is at rock bottom. Recent attacks in Hurghada on the Red Sea have brought violence to the one part of Egypt that had avoided it so far. Of all the destinations you mention I think Egypt has the highest risk - even at popular attractions such as the Pyramids, Luxor and the Red Sea resorts.
But against this backdrop can I say the actual risk of being involved in a "terrorist" event is extremely slim. You have to be in the wrong place at exactly the wrong time.
I suggest you speak to your tour provider about security measures they have put in place. Speak to your travel insurer about coverage in the event of an incident. Check your government's travel warnings for your destinations. Then make up your own mind about the level of risk you are willing to accept. over 3 years ago