Israel forced the Flotilla into Ashdod, not just to inspect the cargo, but also to confiscate any materials which they had banned, such as cement. Since cement was a principal part of the cargo, it would have been foolish to accede to Israeli demands. One of the two main reasons for the Flotilla was to take banned materials into Gaza. Weapons were not part of the cargo. Passengers on the Mari Marmara defended their ship against the IDF attack, as the were legally entitled to do..
NATO backs Turkey's fight against ISIS (Reuters)
from the article: UN rights body names team to probe Gaza flotilla raid