The next 10 years will be a critical time of transition for the U.S. Navy, the service's top officer said -- one that leaders must get right to stop China and Russia from controlling the conditions at sea.

Chief of Naval Operations Adm. Mike Gilday on Monday released his vision for the Navy's decade ahead. Citing a long-term competition that "threatens our security and way of life," he said the Navy must ditch platforms it no longer needs to invest in new tools that will be required to deter aggression and preserve freedom of the seas.

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"I don't mean to be dramatic, but I feel like, if the Navy loses its head, if we go off course and we take our eyes off those things we need to focus on ... I think we may not be able to recover in this century," Gilday told reporters Friday, ahead of the document's release. "Based on the trajectory that the Chinese are on right now -- and again, I don't mean to be dramatic -- I just sense that this is not a decade that we can afford to lose ground."

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The Navy will need to divest itself of several legacy capabilities that Gilday said no longer bring sufficient power to the fight. It will also delay plans to bring large unmanned surface ships to the fleet by a few years, he said.

"This is a very deliberate approach," the CNO said. "... I am more interested in getting it right in a deliberate fashion than I am getting it fast."

The Navy has faced pushback from Congress in recent years over a plan to invest heavily in shipbuilding to grow the size of the fleet, including plans to spend $2 billion on 10 large unmanned surface vessels by 2025. Now, Gilday is slowing that down, saying he doesn't want to rush the purchase of drone ships.

Buying large numbers of unmanned vessels by the mid-2020s is "unrealistic," Gilday told reporters. Instead, by the end of the decade, sailors "must have a high degree of confidence and skill operating alongside proven unmanned platforms at sea," he said.

Gilday also said the Navy must also ditch past programs that don't fit into the Navy's fundamental missions: sea control and the ability to project power forward.

"This includes divestment of experimental Littoral Combat Ship hulls, legacy Cruisers, and older Dock Landing Ships," he wrote. "It also includes divesting non-core Navy missions like Aegis-ashore. Transferring shore-based Ballistic Missile Defense sites to ground forces enables Sailors to focus on their core missions at sea and frees up resources to increase our lethality."

Gilday said he expects criticism over plans to slow large unmanned surface vessels buys at the same time aging Ticonderoga-class cruisers head into retirement.

"It may not be as smooth of transition as everybody wants," he said, "... [but] we need to divest from some of these capabilities that are becoming very expensive to maintain."

The Navy is transforming at a time when military leaders are bracing for possible budget constraints. Gilday said he doesn't expect any sort of plus-up. President-elect Joe Biden has acknowledged that the military is facing threats it hasn't seen since the Cold War, but slammed President Donald Trump for abandoning fiscal discipline when it came to defense spending.

Biden has called for smart investments in new technology needed for the future fight -- ramping up spending on innovation and moving away from investing in yesterday's equipment that won't be able to compete against stronger adversaries.

Gilday's plan says the Navy must improve its "advantages over China before addressing other challenges." That means a bigger, more lethal fleet, he adds, with more submarines, smaller and more numerous surface combatants, stronger offensive capabilities, and unmanned platforms.

"Balancing the requirement to field the future fleet, while maintaining the sustainable forward posture that keeps Americans safe and prosperous, is our central challenge," he wrote.

Gilday said the results of the analysis that led to former Defense Secretary Mark Esper's plan for a 500-ship fleet are important, but added that what they are capable of is more important than the number of ships. He said he wants to see Navy leaders review that analysis at least every other year to update it.

"I don't want to have a force-structure analysis that's three or four or five years old, that's going to sit on the shelf," he said.

With China and Russia rapidly modernizing their militaries, Gilday said there is no time to waste in pushing ahead with the Navy's plan. That includes necessary investments in public shipyards, dry docks, maintenance facilities and aviation depots that he says are overdue for upgrades.

"We are refurbishing these facilities over the next two decades to ensure we can build and sustain our ships, submarines and aircraft for the years ahead," he said.

-- Gina Harkins can be reached at gina.harkins@military.com. Follow her on Twitter @ginaaharkins.

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