So , Israel has been earching for evidence of a secret weapon program for years - what does it say if after all of this time they have no proof ?

http://www.ynetnews.com/articles/0,7340,L-4207265,00.html

Report: Israeli soldiers scour Iran for nukes

Israel using permanent base in northern Iraq to launch intelligence missions in Iran in search of nuclear evidence, Western intelligence sources say

Ynet

Published:  03.25.12, 08:08 / Israel News

Israel is using a permanent base in Iraqi Kurdistan to launch cross-border intelligence missions in an attempt to find “smoking gun” evidence that Iran is building a nuclear warhead, the Sunday Times reported Sunday.

According to Western intelligence sources, Israel has used sensitive equipment during its covert operations to monitor the radioactivity and magnitude of explosives tests. It was also reported that Israeli special forces used Black Hawk helicopters to carry commandos disguised as members of the Iranian military and using Iranian military vehicles.

The sources said that Israel had been conducting intelligence missions in the area for several years. In recent months efforts aimed at the Parchin military complex near Tehran to which the International Atomic Energy Agency (IAEA) has been denied access, have intensified.

According to the sources, operations are also aimed at Fordow near the city of Qom where Iran is working on high-level enrichment.

“We’ve detected clean-up efforts recently in Parchin which might indicate that the Iranians are trying to hide evidence of warhead tests in preparation for a possible IAEA visit,” said a western source.