They are the forces behind the latest rocketattacks against Israel and todays bomb in Jerusalem. Hamas etc. is only a pawn in their game. The reason is to distract the opposition in their countries and the world from their inferior problems and riots for democracy. The connection to what now is happening in Syria and the terrorattacks against Israel is to clear for anyone to miss.
Syria denies targeting refugee camp; UN condemns "murderous attack" (Reuters)
from the article: Bomb explodes in central Jerusalem; 1 dead, at least 30 hurt