I believe those foreign element have been successful, till a few months/weeks ago, we were against Hindu temples, then came prophet cartoons, then anti sahaba speeches, then anti Shia marches, then this murder (plus Nawaz/diesel speeches). Now the sunnis will he glad when a Shia ulema is killed, and the tit for tat game goes on. This happened exactly in Musharraf era.
The only ones responsible are us, we are emotional and less logical in our approach to life, we are a biased nation and till we don't become an all inclusive society we will continue to face these conspiracies.