For the next seven days, America’s Navy is celebrating Dallas-Fort Worth Navy Week to demonstrate and explain how the service, “The Global Force for Good,” impacts your life every day.Dallas-Fort Worth has a long Navy heritage, dating back to World War II when primary flight training took place at Naval Air Station Dallas. Today, NAS Fort Worth JRB is a vital installation. Our newest fighter aircraft, the F-35 Lightning, is being manufactured in Fort Worth at Lockheed Martin, and in 2012 we commissioned the USS FORT WORTH, then the newest model in our most modern class of warships.The Navy protects and defends America on, under and over the world’s oceans. Navy ships, submarines, aircraft and, most importantly, tens of thousands of America’s finest young men and women (many from North Texas) are deployed around the world doing just that. They are there now. They will be there when we are sleeping tonight. They will be there every Saturday, Sunday and holiday this year. They are there around the clock, far from our shores, defending America at all times.Seventy percent of our planet is covered by water. Presence means having the ability to act from the sea. With our aircraft carriers, we don’t rely on access to another nation’s runways; we bring our own. The world’s oceans give the Navy the power to protect America’s interests anywhere, and at any time.When our national security is threatened by the existence of a weapons facility or a terrorist camp on the other side of the world, presence matters.Where these threats exist, chances are high that Navy assets are close by, with the ability to destroy targets located hundreds of miles inland. When the decision is made to act on one of these threats, the solution may involve launching attack jets from carriers, firing cruise missiles from ships or submarines, or inserting a team of Navy SEALs to do what only Navy SEALs can do. In any scenario, your Navy provides all these options and can execute them from the sea, without the need to get another country’s permission to operate within its borders.Ninety percent of world commerce arrives by sea. When piracy threatens innocent lives and disrupts shipping traffic in the Indian Ocean, or rogue nations threaten to deny access to vital ocean chokepoints blocking goods manufactured in Dallas-Fort Worth, presence matters. America’s Navy is there, ensuring the free flow of global trade and, in turn, preserving America’s economic prosperity. Following a humanitarian crisis, like the devastating typhoon that struck the Philippines in 2013 or the tsunami that ravaged northern Japan in 2011, presence matters. Because the Navy is always deployed around the world, it can provide nearly immediate humanitarian relief in the wake of a disaster, ferrying supplies, medicine and trained medical personnel ashore from Navy ships via helicopters and landing craft.When narco-traffickers use speedboats and rudimentary submarines to ferry illegal drugs across the oceans and into America, presence matters. Navy ships and submarines patrol the waters near Central and South America with law enforcement agencies to intercept shipments of illegal narcotics before they reach our shores.As the world’s geopolitical and economic climates continue to evolve, the case for America maintaining a strong Navy grows. Indeed, the president’s national security strategy calls for a renewed focus on enduring threats in the Middle East region, as well as an increased American commitment in the Asia-Pacific region — a vast, mostly ocean-covered area of the world ideally suited for operations from the sea, and in which the Navy maintains a robust presence. This week, we encourage North Texans to come out and witness the thrilling Blue Angels flight demonstration team, enjoy the Navy Band, learn more about our capabilities and, most importantly, meet your sailors. When it comes to defending America, presence matters, and America’s Navy is already there. Juan Garcia is assistant secretary of the Navy.