Sand Castle is not an easy film to review in terms of gauging it against other high adrenaline, fast paced, action filled war movies.
That is not to say the film was not worth watching. It certainly is. Avoiding any spoilers here, the story moves at a rather slow pace for a war film but has a definite message to deliver and does so with finesse and realism. The acting is very strong from each of the characters and the Direction does not overdo the story by muddling it with unnecessary and gratuitous violence. Of course there is a degree of "war time" conflicts and shows its affects on the soldiers who live with it during their tour.
To add to the credibility of the film, the writer (an actual veteran of the 2003 Invasion of Iraq) simply conveys his experience while serving there. I liked this approach to the Genra as it tells a story of a simple objective which becomes difficult due to the nature of war itself and the unfortunate casualties that suffer because of it. It also shows the human cost to both sides, the U.S. Troops as well as the people caught up in the terrible circumstances of war. I felt it illustrates that perspective quite well.
If you looking for a "Platoon" or "Black Hawk Down" type film, this is not for you. But, if you are interested in a film that successfully portrays the life's of all people affected by war, even if the story line does not center on the most brutal and violent ways, this is a film worth watching.