Women are bound for perhaps thousands of combat roles amid a mandated, military-wide integration, but the armed forces’ most coveted jobs — including Navy SEALS and Army Rangers — could remain segregated, male-only preserves largely due to concerns about sex, according to former special operations troops.

Some ex-military members contend sexual attractions and relations are inevitable if male and female Special Ops members are placed in self-contained groups (as small as 12 or two) for long periods in lonely places. Those encounters, they add, could spark competition, jealousy and general havoc within tight teams where mutual trust and a laser attention to detail keep those troops alive.

Brandon Webb, a former Navy SEAL who deployed to Iraq and Afghanistan, contends that potentially disruptive hookups will occur if women are assigned to what are now all-male Special Ops teams: “How do you practically expect men and women not to have sex together under extreme stress, a half a world away from America — and how does that affect unit effectiveness?”

While the major branches each have submitted precise plans to test, train and assign some women to combat by 2016, leaders of U.S. Special Operations Command won’t yet commit to opening their 15,497 jobs to females. They cite a certain disquiet — from the top of that exclusive service to the guys on the ground — about “culture” and “behavior” pitfalls potentially linked to integration.