Now in its sixth year, the crisis has destroyed the fabric of life in Syria, killed at least 400,000 people, triggered the worst human displacement crisis since the end of World War II, put neighboring countries of first asylum under enormous pressure, exacerbated regional tensions, and helped swell the ranks of violent extremist organizations, most notably Daesh and al-Qaeda. The conflict continues to be fueled by patrons and proxies with divergent interests and priorities at a time of unprecedented upheaval across the wider Middle East, as governments pursue new models of political rule and vie for new positions of regional influence. In short, the Syrian conflict presents one of the most complex challenges we have faced. There is no way to look at what is happening on the ground in Syria and not feel profound grief and horror. In the midst of such tragedy, it is tempting to want a neat answer that ends the civil war and eases suffering overnight. But the challenges before us defy silver bullet solutions. The United States is clear-eyed about our role and responsibility. The civil war in Syria is not about us, nor can it be solved solely by us. But it challenges our security and strategic interests-and moral values.