It's actually quite common for commercial cruise ships to be on call for a country's military needs, and they are primary used for for transporting troops.
The media freaked out about China’s crappy aircraft carrier and hyperventilated over the J-20 stealth fighter. But China’s newest addition to its military is more subtle, and stylish. It’s a 36,000-ton pleasure boat capable of disgorging thousands of troops and hundreds of vehicles held inside its belly.
That would be the Bahai Sea Green Pearl, a 36,000-ton ferry and cruise ship commissioned in August at Yantai Port in China’s northeastern Shandong Province. At heart a vessel for pleasure and civilian transport, the ship is intended to normally ferry cars and passengers across the Yellow Sea. But when needed by the People’s Liberation Army, the Green Pearl can double as a troop carrier. During its launching ceremony and demonstration on Aug. 8, PLA troops could be seen loading dozens of tanks, artillery pieces and armored vehicles on board.
It’s also got luxury. When the ship isn’t ferrying civilians, China’s troops could take in the pleasure of tall windows for observing “the beautiful scenery of the sea,” reported the Yantai Daily Media Group. Not only that, but rooms — which range from first to third class — are equipped with televisions, cellphone signal amplifiers and wireless internet access.