The China EP-3 incident is putting the spotlight on several military issues that have previously been in the shadows. For example, while China does not use electronic surveillance aircraft, they do have several ships that perform this duty (as does the U.S., Russia and several other nations.) In the past year, both Japan and the Philippines have complained about Chinese electronic surveillance ships coming into their territorial waters (within 12 miles of the coast, the internationally recognized standard.) China denies everything, or insists that they were outside the twelve mile limit. China claims a 200 mile limit.
As soon as the EP-3 crew were safely out of China, the US began releasing embarrassing photos and videos of Chinese jets flying close (too close for safety) to earlier US recon flights. These close ups revealed something rather more embarrassing. It seems the J-8s were carrying Israeli Python air-to-air missiles. These weapons are much more effective and reliable than anything the Chinese could build themselves or get from Russia. It had long been rumored that Israel was secretly selling China weapons, electronics equipment and technology over the last twenty years. These sales are kept quiet because otherwise American officials would be asked embarrassing questions about why we give Israel $3 billion a year and share military technology, while Israel sells weapons to a potential U.S. enemy.
The Chinese probably knew that the EP-3 they had was recently upgraded with new equipment. As a result, they feared a commando raid to retrieve, or destroy, the aircraft. As a result, the Chinese moved concrete barriers out onto the runway at night to make it more difficult to fly the EP-3 away, or for commandoes to land. Apparently a commando raid was considered, but only if it was discovered that the EP-3 crew were being mistreated. The Chinese, perhaps realizing this, openly treated their American prisoners quite well.
One bit of new U.S. technology that the Chinese probably found intact on the EP-3 was the new, military grade, shredders. These high performance items not only shred paper, but also destroy CD data disks and floppy disks.