Amanda Catanzano is senior director of international programs -- policy and advocacy at the International Rescue Committee. The opinions in this article belong to the author.

(CNN) 2017 will mark the sixth anniversary of the Syrian conflict -- a war that has left nearly half a million dead and forced millions of others from their homes.

The new year brought a ceasefire brokered by Russia, Iran and Turkey. But the ceasefire is serving as cover for "business as usual." The Syrian government continues to use illegal means of war to crush political opponents and citizens , forcing them to accept an uncertain and unjust "peace." But peace achieved by these means cannot, and will not, hold.

Aleppo: 'The soul of the city is still there'

Aleppo: 'The soul of the city is still there' 04:37

Aleppo: 'The soul of the city is still there'

This should come as no surprise. Fundamental flaws are baked into this agreement. Major parties to the conflict did not sign on to the ceasefire . It allows President Bashar al-Assad and his Russian and Iranian allies to label all opposition groups as terrorists.

At the same time, more than two-thirds of Syrian territory remain outside of Assad's control. Syrian military assaults continue, with civilians not just caught in the crossfire -- but deliberately targeted.

Predictably, the truce is fraying already , with opposition groups crying foul as Syrian forces continue to pound rebel-held areas around Damascus and beyond.

The international community must take four steps to ensure that civilians stop paying the price of ending the war.

UN monitors cannot be an afterthought

The Aleppo model for victory is not acceptable.

The Syrian military and its allies deliberately targeted civilians, hospitals and schools, using starvation and the denial of medical care as weapons of war that brought the city to its knees.

The UN Security Council's decision to introduce monitors into eastern Aleppo was overdue and incomplete . Hundreds of thousands of civilians, forced to evacuate to Idlib province -- another contested area -- wait in fear of the same brutal attacks and siege tactics.

Last week, the Syrian regime signaled its readiness to conduct such Aleppo-style attacks, with a senior official calling for "open battle" in Idlib . The presence of al Qaeda and other terrorist groups in Idlib complicates matters -- giving Assad and his allies "cover" for such attacks. But to be clear, the Syrian government is not focused on fighting terrorists but on combating opposition to Assad wherever it is found.

To protect Syrian civilians and ensure agreements made by parties to the conflict are upheld, the Security Council should expand the monitoring team's mandate into these contested areas. No victory can be claimed in the context of such human suffering. No victory can be held in the context of such injustice -- it will only sow the seeds of future opposition.

Clear accountability for violations of international humanitarian law

Last month, the UN General Assembly stepped in to address the impunity that has driven the ceaseless violations of international humanitarian law in Syria. It called for a team to "collect, consolidate, preserve and analyze evidence" of war crimes in Syria.

The international community, including the incoming Trump administration, should support and strengthen this General Assembly proposal through the creation of a concrete and meaningful mechanism for accountability. The road to justice is long, but the international community must begin to pave it. Otherwise, we are simply sending a message to despots and dictators everywhere they can behave with impunity.

A political settlement remains fundamental

The Assad regime may be able to carve out a portion of Syria that it can "govern" with some stability, but the violence facing civilians is not over.

Violence is not just inevitable in Idlib and other opposition-held areas. ISIS continues to capitalize on the chaos -- as it did in the Syrian city of Palmyra while Assad's forces were distracted in Aleppo. Increased investment in political dialogue with rebels and their external backers remains the only long-term path to a whole-of-Syria peace. Regional players will need to negotiate and compromise.

Without humanitarian access there is no peace

And without peace, humanitarian access will remain politicized. There remain dozens of besieged enclaves -- including eastern Ghouta, a key region east of Damascus, where more than 250,000 people have been blockaded for four years.

Political will is necessary to make progress on humanitarian access and aid delivery. As mandated by the Security Council, this is an opportunity for the new US administration to work with Russia and regional players to ensure sustained and sufficient humanitarian access into all populations in besieged areas.

Follow CNN Opinion Join us on Twitter and Facebook

The laws of war and primacy of civilian protection, drawn from the worst of human experience, are being disregarded at tremendous cost. The world's leaders must fight for them in order to contain and resolve the conflicts at the heart of regional and global instability.

The incoming Trump administration has promised an unpredictable foreign policy, but these circumstances call for predictability and consistency. The new administration, as well as other global leaders, must show that some things will not change. If not, Syria will continue to be the greatest indictment of humanity in the 21st century.