Click to expand Image Deminers search for landmines near Lasinja, a village 40 kilometers south of Zagreb, Croatia, May 29, 2013. © 2013 Sipa via AP Images Since the 1990s conflicts in the Balkans, Croatia suffered from the scourge of landmines, with hundreds of civilians killed and thousands of acres of land inaccessible due to contamination. In March, the country celebrated becoming mine-free, following a US$1.38 billion, 30-year clearance campaign.Croatia’s story underscores the value of the Mine Ban Treaty and should encourage more countries to join and promote its goals. But on this International Day for Mine Awareness and Assistance in Mine Action, the treaty faces threats from countries withdrawing and from new use of the weapons.Croatia’s heavy contamination stems from 1991-1995, when the main parties to the conflict used landmines. More than 20 percent of the country was contaminated, barring communities from returning and resulting in an annual economic loss of at least $230 million.Interior Minister Davor Božinović said, “This is not just a technical success—it is the fulfillment of a moral obligation to the victims of mines and their families. A mine-free Croatia means safer families, better development of rural areas, more farmland, and stronger tourism.”These successes, a testament to the dedicated work of deminers and sustained government interest, are exactly what the treaty aims to achieve, and the International Day celebrates.Yet, rather than learning from the experiences of Croatia and the more than 30 mine-affected states parties to the treaty that have cleared their land, some countries have abandoned the effort.In the past year, Latvia, Lithuania, Estonia, Finland, and Poland withdrew from the treaty, contending that antipersonnel landmines were necessary to protect themselves from Russian aggression. In July, Ukraine also sought to unlawfully suspend its obligations under the treaty.New use of antipersonnel landmines in Myanmar, Russia, and Ukraine, as well as along Iran’s borders with Afghanistan and Pakistan, North Korea’s border with South Korea, and the contested Thailand-Cambodia border threatens the norm against these weapons.The International Day for Mine Action affords an opportunity to reflect on the horrific impact of antipersonnel landmines on civilians, the significant improvement in civilians’ lives the treaty has achieved, and the importance of upholding and bolstering opposition to their use. States not party to the treaty should join. All countries should oppose their use and help fund clearance and assistance for victims.