As the opening of the American embassy in Jerusalem plainly shows, the U.S. is going to be more closely linked to Israel including especially its security. Since the 1960s, Israel has concentrated its attention on ground and air forces. Because of new technology, Iran’s nuclear and ballistic missile programs, and Russia’s increased naval presence in the region to name a few, Israel—today and in the future—will have to look to the seas to defend itself.

Israel’s maritime strategy is not fully formed, nor is its outline detailed. This matters not only to Israel but to the U.S. which retains a vital interest in free navigation in the Mediterranean and the stability that powerful naval forces in the region help assure. The U.S. shares an interest with Israel in denying use of the seas to terrorists; and preventing the hegemonic power that Iran and Turkey seek. A robust Israeli navy and maritime strategy benefit the U.S. whose permanent presence in the Med is based in Spain and has been reduced to four ballistic missile defense destroyers where once two aircraft carrier groups and a large Marine amphibious ready group patrolled.

The Med has reverted to its historic template: the tensions and conflict that have characterized the area from the Trojan War to the Cold War are back. In the Eastern Mediterranean Russian naval presence is growing, the Lebanese state has become increasingly enthralled to the Iranian-backed Hezbollah terror organization while Iran regards Syria as another instrument to threaten the Jewish state. Turkey recently signed an agreement to build a naval base in the Iran-friendly Persian Gulf state of Qatar and continues to distance itself from NATO, and Chinese investments in the region are accelerating, as are the naval deployments of Iran.

Israel’s national security is at risk not only from attacks that Hezbollah, Hamas, and Iran might launch from the land. The seas also offer Israel’s enemies opportunities to inflict serious damage.

More than half of Israel’s population lives on or near the coast, for example in the large cities of Tel Aviv and Haifa, and the thin strip of land between them. Also on the coast are shore-based energy plants, and at sea—at least for now—a single natural gas drilling rig. In September 2017 a reported crack in one of the Tamar rig’s pipes cut the flow of natural gas to Israel by half until it was repaired five days later. The Tamar natural gas field supplies well over half of Israel’s energy needs.

Since natural gas deposits were discovered in Israel’s exclusive economic zone (EEZ) beginning in 2000, the country’s use of natural gas has increased eight-and-a-half times. The likelihood that this growth will continue is good, along with the rigs to extract it. The existing natural gas rig and those that may be added in the future lie within Israel’s EEZ.

Fish provide an important element of protein in an Israeli citizens’ diet—a signification portion comes from Mediterranean fisheries. Ninety percent of Israel’s commerce travels by sea.

For a nation that possesses no strategic depth, the seas also provide an indispensable deterrent against nuclear attack in the form of submarines that can assure retaliation against a potential nuclear aggressor—like Iran. The stealth of submarines is excellent protection. However, stealth is not a guarantee. Even stealthy submarines can be vulnerable, and any state that depends on them for deterrence must live with that vulnerability.

Israel’s domestically-produced Iron Dome missile defense system has an impressive operational record. It is part of a multi-layered missile defense that includes the David’s Sling medium-range anti-air and anti-ballistic missile, the Arrow anti-ballistic missile, and U.S.-made Patriot missiles. This array can destroy rockets, aircraft, and unmanned aerial vehicles as they become more widespread. Protecting against sea-borne threats is at least as great a challenge.

Shore-based anti-ship rockets and shore-to-sea cruise missiles can be launched at Israeli naval vessels—as one was in 2006 when a Hezbollah-launched missile fired from the Lebanese coast struck a Sa’ar 5-class corvette. The Chinese-designed Hezbollah missile traveled 10 miles to find its target. It has a 75-mile range.

To the south, five Hamas naval commandos from Gaza tried unsuccessfully in 2014 to penetrate Israeli defenses to attack nearby Kibbutz Zikim.

Iranian access to Syrian ports would add the Iranian Revolutionary Guard Corps’ asymmetrical naval arm to threats from the sea that Israel must face. These include but are not limited to swarming small boats, maritime suicide attackers, midget submarines, naval commandos, and mines.

China has recently built a naval base in Djibouti along the southern approaches to the Red Sea. This extends China’s ability to project naval power nearly 6,000 miles from home and brings nearer the day when Chinese naval power will be a part of the Middle East’s naval balance.

Israel faces the prospect of a naval encirclement from small-scale, numerous, and widely diverse dangers that threaten its people, critical infrastructure, energy, commerce, and ability to devote undivided attention to its enemies’ land-based attacks in a coordinated land and sea strike.

Jerusalem understands, in part, the seriousness of the growing naval threat. Since 2013, Israel has purchased eight Seahawk SH-60 helicopters, three Dolphin-II submarines, and four Sa’ar 6-class corvettes. During the same period, the Israeli navy has refitted its Sa’ar 4.5 class corvettes with state-of-the-art radar systems, deployed new Protector Unmanned Surface Vehicles, and has put the Iron Dome missile defense system aboard navy ships.

However, while making sure that the Israeli navy’s size, composition, and balance are sufficient, a clear statement of maritime strategy would improve Israel’s security. The objective is security for the close-in waters of a concave arc that stretches from Haifa through the western reaches of the Sinai to Eilat and the Red Sea. This would defend population centers, infrastructure including natural gas rigs, and other coastal targets. It would be Israel’s first line of maritime defense.

A perimeter defense is also needed. Its presence in an area from Crete to the Mediterranean coastline and from the international waters south of Mersin in Turkey to Port Said will grow in importance as hostile navies increase their Eastern Mediterranean combat fleets.

Because of Israel’s proximity to its hostile neighbors—Hezbollah-dominated Lebanon, Hamas-controlled Gaza, and Iran’s Syrian puppet—the Israeli navy has the task to respond to threats, almost instantly. If enemy vessels bearing down on a natural gas rig aren’t stopped quickly, Israel’s economy and security could be seriously harmed. Shore-based anti-ship missiles can help, as can point defenses on drilling rigs. The same shore-based missiles can—and should—play a major role in providing air cover for Israeli ships at sea.

But these are not a substitute for swift, lethal combat vessels on the scene that can sink an attacking enemy. The threat of retaliation at some point in the future won’t do, nor is it consistent with the Israeli style of warfare which favors swift response. A strategy of deterrence by denial—that is the ability to inflict immediate and substantial pain against attacking vessels or mine-layers, and the ports from which they and special operations forces emerge—is needed to stop attacks and even better, deter them. The Israeli air force and special operators can handle pre-emptive or retaliatory strikes against most enemy targets deeper inland.

A robust system of intelligence, surveillance, and reconnaissance (ISR) is crucial for a strategy that is based on deterrence by denial. Shore and sea-based platforms can provide this capability. Underwater sensing systems—that detect surface and subsurface vessels—would also improve the Israeli navy’s ability to identify approaching threats. Even where there is strategic depth, effective ISR is critical.

Another vital defensive instrument is mine-sweepers. As the old saw goes, “how many mines does it take to create a minefield?” The answer is ‘zero.’ If naval commanders believe that a minefield exists, they will act with the caution that impedes swift response. Besides offensive capability as a deterrent, the Israeli navy will increase Israel’s maritime security substantively with the ability to ensure its safety and that of its merchant shipping.

Finally, there is the possibility eventually of relatively large Turkish and Iranian naval vessels, combatants whose firepower could threaten the Israeli navy at sea, offshore energy infrastructure, and Israeli civilian and strategic targets inland from the Mediterranean coast. Submarines, underwater drones, existing surface and aerial drones, and a small number of frigate—or destroyer-sized combatants--combined with an enlarged fleet of corvettes are needed to prepare for these more conventional naval threats. None of this is cheap. A successful naval envelopment of Israel by hostile states is far more expensive.

Additional support could be sought from the interoperability that leads to naval alliances or partnerships with two neighbors. Cyprus’ natural gas discoveries in its EEZ are also at risk from Turkish military/naval action. Greece’s navy protects the offshore region south of Cyprus where natural gas has been found and is currently being explored for additional deposits. A shared concern about Turkish aggression and the protection of natural gas helped build the current warm relations between Jerusalem and Athens.

Similarly, very large natural gas deposits have been discovered in Egypt’s EEZ. Both Greece and Egypt have an interest in protecting their natural gas assets. Israel should be prepared to go it alone but could benefit greatly by seeking regional partnerships based on a shared interest in defending against Turkey and Iran respectively.

Current leadership—President Erdogan—makes Turkey a wild card. But it was not so long ago that Israeli-Turkish relations were solid, and economic ties between Israel and Turkey are largely intact. A future change in Turkey could resuscitate the relationship that served both nations well. However, for now, Ankara remains sufficiently problematic to regard Turkey as a potential threat in crafting Israel’s maritime strategy.

There are historical precedents for a maritime strategy composed of high-tech, small vessels. In the early 19th century, French naval planners developed what would become known as the Jeune École concept of naval warfare. Based on smaller naval combatants and highly skilled crews, the intent was to deploy large numbers of technologically-advanced, steam-propelled small vessels to counter England’s high-displacement battleships. The French navy used these combatants and accompanying tactics successfully against China in the 1880s.

More than two decades later, the great British naval innovator Admiral Sir “Jackie” Fisher was sufficiently impressed to initiate a new class of capital ship with lighter armor and powerful guns that could maneuver more easily than the great battlewagons. High speed and superior lethality are useful against smaller combatants and the more remote possibility of larger ones.

Israel has very high-quality and skilled sailors. Like 19th century France, it possesses advanced technological skills. Marrying these two strengths is as useful in defeating terrorists at sea as it applies to defending against conventional ships.

An Israeli maritime strategy should consider how best to draw on Israel’s human and technological strengths for superior weapons, platforms, and sensors.

The strategy can prescribe a layered defense that consists of ISR and surface vessels able to sink enemy ships by outrunning and outgunning them. This requires sufficient strength in deployed combatants to deliver immediate lethal power to destroy or cripple an enemy’s shore-based facilities and threaten his infrastructure.

The Israeli navy’s ability to operate constantly with the protection against air and missile threats of its vessels’ systems as well as the Israeli army’s shore-based missile defenses would give Israel the constant presence at sea on which its national security increasingly depends. As threats, especially from Iran, grow throughout the region over time, larger multi-purpose vessels will become necessary. Submarines extend the deterrent power of Israel’s maritime strategy far beyond the range of the Israeli navy’s current surface ships. They are essential. And, so—based on U.S. experience—is a procurement system whose integrity is a condition for the nation’s strategic health.

The questions that face Israel’s naval planners are relatively limited by the geographic scope of the threat and by the current absence of large-state naval actors. A substantial change in the geography that the Israeli navy must cover would complicate matters—for example, Iranian missiles that could be launched from their Houthi clients’ positions at the Red Sea’s mouth.

But for now, the task of an effective maritime strategy is to protect Israel’s interests at sea and its land from naval attack. The U.S. has a major stake in the success of Israel’s sea defense, not only because of our interest in Israel’s overall security and well-being but because we have reduced our own presence in the Mediterranean so dramatically since the end of the Cold War.

There’s ironic humor in the popular Israeli tee-shirt for tourists that says, “Don’t worry America. Israel has your back.” But there’s a valid point there too.

Seth Cropsey is a Senior Fellow at Hudson Institute and director of Hudson’s Center for American Seapower. He served as an officer in the U.S. Navy and as deputy Undersecretary of the Navy in the Reagan and George H. W. Bush administrations.