Netanyahu is simply allowing these types of leaks to further push up gas prices. This, he knows, does more harm to the Kenyan. An attack would have an unpredictable effect on the election. Might even help 0bama.
If the issue is a point in time at which Israel can no longer mount an effective strike, then Israel must strike before that point in time.
If that truly is the issue, then their attitude must be “american politics be damned.”