Many on the Left see the War on Terrorism not as a war of Good versus Evil, but...Muslim resistance to foreigners who seek influence over the region's geopolitical assets and vital resources. This resistance typically takes the form of asymmetrical warfare, e.g., "terrorism". Why? -because long-colonialized regions have been denied the right to develop sophisticated weaponry.
Which is to say: The Left has a different interpretation of the War on Terrorism. They think Washington Bureaucrats strategically use national security threats (real or exaggerated) to insulate their decision making from poular review so they can create policies which, after the damage has been done, fail the smell test, like Iraq.
The Left wants the talk radio listener to think more about the very complex reality of American Power, and how that power has shaped certain regions in ways that occasionally lead to blowback, e.g., attacks against US military, financial, and foreign assets like Israel, the Pentagon, and the Twin Towers. This interpretation doesn't stem from hating America - which is the Right's favorite straw man - rather, the Left believes you can hate a Government policy (like Vietnam Iraq Kosovo Libya or the the New Deal) but still love the country. The ability to disagree with a government policy is the cornerstone of a free society.
The conflation of government policy with "the country" or "the people" is a species of fascism (which the far Right has always been sympathetic to because they are more likely to believe in an inviolable set of absolute, universal values that all must share, typically embodied in a centralized power like God or one of His earthly interlocutors like Ronald Reagan. Does the Rightwing voter ever notice how messianic Reagan, Bush, or Obama sound when they're saving the world from evil barbarians? They are so clearly trying to stamp the harsh realities of geopolitical hardball with a divine mandate)
Getting back to my point about different interpretations. The Left offers historical evidence of how Washington (a place we think you trust too much) has used military, CIA, and economic leverage to over-manage the affairs of others, e.g., Iran 1953; the Carter Doctrine which declared that the US will use military force to protect its energy interests; Reagan's support of Hussein or the mujahideen in the 80s; Reagan arming monsters on several continents from Iran to the Contras; Washington's longstanding financial and weapons support to places like Saudi Arabia & Libya; and a pattern of supporting ruthless regimes so that they will protect our regional interests. Not to mention the dizzying array of Pentagon protected business alliances, like that between Ken Lay and the Taliban when they were trying to run a pipeline through Afghanistan and Pakistan to the Indian Ocean. All of these things add immense complexity to the "good versus evil" narrative told to women, children, and republicans in order to insulate them from the evil men must do in the outlying colonies.
Needless to say: the Left realizes that when Washington Bureaucrats try to control political outcomes in places like (say) Iran, Afghanistan, or Saudi Arabia, there is likely to be harsh resistance, some of which calcifies into violent proto-military groups like Hezzbolla or Al Qaeda.
The Right sees all this conspiratorial geopolitical talk as lies or exaggerations, even though our military and financial support of "bad" regimes is on the official record, and easily researched.
So I agree with the OP that this story is tragic. I also hope the guilty party is brought to justice, harsh justice. I just wish the OP wouldn't accept Washington's framing of The War on Terrorism because we need critical thinkers who understand our long complicated history in the region. We need the OP to have a detailed understanding of the policies that have been initiated at least since Eisenhower. He doesn't.
One of the reasons Washington (since WWII) has been allowed to waste so much blood and money on failed military intervention is because The Bureaucrats have created useful idiots who buy into simplistic stories.