From Foreign Affairs:
According to UN investigations, in 2011, extremist settlers launched almost 300 attacks on Palestinian property, causing over 100 Palestinian casualties and destroying or damaging about 10,000 trees of Palestinian farmers. The UN has also reported that violent incidents against Palestinians have proliferated, rising from 200 attacks in 2009 to over 400 in 2011. The spike in assaults on Palestinians by settlers has come despite the fact that over the same period, Palestinian terrorism fell dramatically.
…The Israeli government does not support or condone settler violence, but it has failed to adequately combat it. Soldiers have been known to look on as violence occurs, and they sometimes do not aggressively seek the perpetrators after the fact. According to Yesh Din, an Israeli human rights organization, of 781 incidents of settler abuse monitored since 2005, Israeli authorities closed the cases on over 90 percent of them without indictment.
Perhaps there is an argument to be made that the fact that Israeli authorities systematically ignore and pardon settler violence doesn’t necessarily equate “support” for it. But that is a weak argument. And it’s even weaker when you consider that Israeli policy purposely incentivizes Israelis to live in the West Bank. Under Prime Minister Benjamin Netanyahu ‘s policies over the last three years tens of thousands more Israelis have moved into the West Bank, causing the Jewish population in Palestinian territory to increase by 18 percent to more than 342,000 at the end of 2011. Israeli spending on these illegal settlements has hit a two-decade high of $1.1 billion. This, while Tel Aviv is well aware of the rise in settler violence.
That certainly sounds like support to me.