In January 2014, the U.S. and Russia’s highest military leaders and their staffs met in Brussels to discuss important security issues. The turmoil in Kyiv’s Maidan Square was intensifying, and the Sochi Olympics and Ukrainian President Yanukovych’s ouster were just weeks away. That was the last time senior U.S. and Russian military leaders met face-to-face — and the end of several years of active, though guarded, engagement between our militaries. It is of urgent importance, particularly in the wake of the horrific attacks in Paris, that our two countries reopen these conduits.

As U.S. defense attaché to Russia, I attended that meeting between Gen. Martin Dempsey, then the chairman of the Joint Chiefs of Staff, and Gen. Valery Gerasimov, still the chief of the Russian General Staff. The discussions, though laced with disagreements over Syria, missile defense and Ukraine, remained cordial, and included mutual concerns such as militant Sunni Islam, Afghanistan-Central Asia, and counterproliferation.

But less than six weeks later, both sides shut down almost all government-to-government contact after Russia illegally annexed Ukraine’s Crimea. Since then, such ties have been limited to sporadic high-level diplomacy, the Moscow Link Presidential “hot line,” and some anti-terrorist, space, and arms control functions.

Our silence and international sanctions were meant to serve notice to Moscow that it had crossed the wrong Rubicon. But that Brussels meeting, unbelievably, was almost two years ago. It’s way past time for senior U.S. and Russian defense leaders and staffs to start meeting again. While never discounting Russia’s aggression against Ukraine, and their sharp-elbowed entry into Syria, it is increasingly dangerous in this cyber-fast world for both our nuclear-tipped nations to have such a dearth of contact.

The reopening of conduits between senior military commanders with regional and global responsibilities would not be “business as usual.” Rather it would be hardnosed practical business: adding some human familiarity at key command-and-control nodes that might keep a sudden accident or incident from flashing into catastrophe. In a fast-breaking crisis, you want leaders who already know each other. And over time, these linkages might help us move beyond these sour political times, and rebuild the kind of relationships that will allow our countries to work on global challenges where we have areas of common interest.

The Obama administration should give Defense Secretary Ashton Carter and the new CJCS, Gen. Joseph Dunford, the political green light to meet for the first time with their Russian counterparts, Defense Minister Sergei Shoigu and General Gerasimov.

Indeed, the Syrian imbroglio presents an opportunity. In the wake of the Paris attacks, it appears that the Russian and U.S. positions in regard to the Syrian regime’s end state and the fate of President Assad are more nuanced than even a month ago. France is also now aggressively involved. Senior diplomats are talking more and the headquarters of the U.S.-led coalition now has a link with the Russians to improve operational safety and communications over Syria. The confirmed destruction over the Sinai by ISIS of the Russian civilian Metrojet airliner also urges more consultation.

There are valid arguments against renewed dialog with the Russian military at this troubled juncture in our relations. Some may suggest a resumption of contacts will merely reward Moscow for their aggressive international behaviors. Others will say we’ll look like supplicants. And others will wonder of what use it might be to talk with people who deceive us. As one exasperated senior U.S. official told me during the thinly veiled Crimean invasion, “It’s frustrating to know that the Russians know that we know they are lying to us. Why bother?”

We should bother because without a dialog of any consequence our strategic defense relationship will be even more dangerous and prone to hair-trigger miscalculation or misunderstanding. Without patient dialog, even if unsatisfying, there will be little chance of better understanding each other’s perspectives and identifying points of convergence within the mud of divergence. Without contact, we both continue to demonize each other while hardening our populations. It’s better agreeing to disagree than having no discussion at all. Without direct dialog between our senior defense leaders we cannot even begin to consider a more mutually cooperative and secure future.