The possibility of someone bringing down an airliner with a SAM missile has been a long-standing source of concern, as reflected in Soyoung Ho’s piece on this subject for the Washington Monthly in April 2003. Back then, though, it was assumed that limitations on missile range meant airliners were only vulnerable for brief periods on takeoff and landing. As Ho noted, technological improvements could change everything:
Advances in missile technology…mean that should terrorists attempt to shoot down an airliner, they’ll be more likely to succeed. The latest models, manufactured primarily by the United States, Russia, Japan, and France, have ranges of over 22,000 feet. That means terrorists can fire from farther away; it also means that airliners are vulnerable during a longer portion of their takeoffs and landings. The new missiles are also more agile, so that, once launched, they’re better able to home in on the target and counter the pilot’s attempts to evade. Finally, they’re able to close in on aircraft from any direction, not just from behind–giving would-be terrorists greater flexibility in choosing a secure place from which to fire.
MH17 was apparently cruising at 33,000 feet, which would have made it safe from missiles until very recently. Clearly airline protocols need to keep up with technology and the lethal intentions of those deploying it.