SAN DIEGO ó The head of the Marine Corps says itís time the U.S. military branch known for its fierce, young warriors becomes a little more mature. The Marine Corps is considering offering bonuses and other perks to entice older, more experienced Marines to re-enlist as it builds up its cyber operations to defend the nation, especially against cyberattacks from Russia and China. About 62 percent of Marines are 25 years old or younger with many serving only four years. The move marks a historical change that could transform a force made up primarily of high school graduates lured by the bravado and physical challenges of joining a branch that prides itself on being the "tip of the spear," the first to go into battle and knock in doors. Itís part of the Marine Corpsí modernizing efforts after 16 years of largely low-tech, counterinsurgency fights. "Itís going to be a Marine Corps thatís a little bit older, a little more experienced because as much as we love our young Marines Ö we need a little bit older because it takes longer to learn these skills," Gen. Robert Neller told defense leaders at a San Diego conference. "And so weíre an organization looking at the whole way we do business, and itís going to change our culture." Marine Corps officials are quick to emphasize the core recruiting mission will remain the same for the branch that boasts having the toughest warriors in the U.S. military. But getting more Marines to re-enlist could inadvertently ease pressure on recruiters. Less than 30 percent of the U.S. population is qualified physically, mentally and morally to serve, according to military leaders. A greater number of older Marines could also help lessen behavior problems like excessive drinking that can be more prevalent among junior Marines. "By older Marines, weíre not talking guys with walkers but rather second- and third-tour enlisted Marines," said Gary Solis, a military expert at Georgetown University who served 26 years in the Marine Corps. "They may be only a few years older than the 18- and 19-year-old Marines, but those three or four years difference could make a hell of a difference as far as maturity when it comes to their outlook and unit cohesion." The 2018 defense budget earmarked money for the Marine Corps to add 1,000 Marines, many of whom will work in cyber and electronic warfare. The Marine Corps is opening jobs this October in its new cyberspace occupational field. After the announcement of the field, Neller tweeted: "íTrigger fingers turn to Twitter fingersí? Not exactly, but this is the next step in professionalizing our cyber force, which will be critical to our success, now and in the future."