Two years after the raid on Osama bin Laden’s hideaway, terrorism alarmists remain in peak form explaining that although al-Qaeda has been weakened it still manages to present a grave threat.

Various well-honed techniques are applied to support this contention. One is to espy and assess various “linkages” or “connections” of “ties” or “threads” between and among a range of disparate terrorists or terrorist groups, most of which appear rather gossamer and of only limited consequence on closer examination.

Another is to exaggerate the importance and effectiveness of the “affiliated groups” linked to al-Qaeda central. In particular, alarmists point to the al-Qaeda affiliate in chaotic Yemen, ominously hailing it as the “deadliest” and the “most aggressive” of these and a “major threat.”

Yet its chief efforts at international terrorism have failed abysmally: an underwear bomb and laser printer bombs on cargo planes. With that track record, the group may pose a problem or concern, but it scarcely presents a “major threat” outside of war zones.

More generally, “al-Qaeda is its own worst enemy,” as Robert Grenier, a former top CIA counterterrorism official, notes. “Where they have succeeded initially, they very quickly discredit themselves.”

Any terrorist threat within the developed world seems even less impressive. The Boston terrorists of 2013 were the first in the United States since 9/11 in which Islamist terrorists actually were able to assemble and detonate bombs — albeit very primitive ones. But except for that, they do not seem to have been more competent than most of their predecessors.

Amazingly, they apparently thought they could somehow get away with their deed even though they chose to set their bombs off at the most-photographed spot on the planet at the time. Moreover, they had no coherent plan of escape and, as commonly found, no ability to explain how killing a few random people would advance their cause.

While the scope of the tragedy in Boston should not be minimized, it should also be noted that if the terrorists’ aim was to kill a large number of people, their bombs failed miserably. As recent cases in Colorado and Connecticut sadly demonstrate, far more fatalities have been inflicted by gunmen.

Before Boston, some 16 people had been killed by Islamist terrorists in the United States in the years since 2001, and all of these were murdered by people who were essentially acting alone. By contrast, in the 1970s, organized terrorists inflicted hundreds of attacks, mostly bombings, in the United States, killing 72.

As concern about organized attacks has diminished, fear of “lone wolf” attacks has grown in recent years, and one official assessment contends that “lone offenders currently present the greatest threat.”

This is a reasonable observation, but those concerned should keep in mind that, as analyst Max Abrahms has noted, while lone wolves may be difficult to police, they have carried out only two of the 1,900 most deadly terrorist attacks over the last four decades.

The key question, at least outside of war zones, is not, “are we safer?” but “how safe are we?”

At current rates, an American’s chance of becoming a victim of terrorism in the U.S., even with 9/11 in the calculation, is about 1 in 3.5 million per year. In comparison, that same American stands a 1 in 22,000 yearly chance of becoming a homicide victim, a 1 in 8,000 chance of perishing in an auto accident, and a 1 in 500 chance of dying from cancer.

These calculations are based, of course, on historical data. However, alarmists who would reject such history need to explain why they think terrorists will suddenly become vastly more competent in the future.

But no one seems to be making that argument. Indeed, notes one reporter, U.S. officials now say that al-Qaeda has become less capable of a large attack like 9/11. But she also says that they made this disclosure only on condition of anonymity out of fear that “publicly identifying themselves could make them a target” of terrorists.

In contrast, one terrorism specialist, Peter Bergen, has observed in heroic full attribution mode that, “The last terror attack (in the West) was seven years ago in London,” that there “haven’t been any major attacks in the U.S.,” and that “they are recruiting no-hopers and dead-enders.”

Terrorists do, of course, exist — as they have throughout history. They may even get lucky again sometime. Thus, concern and watchfulness about terrorism is justified. But counterterrorism expenditures that are wildly disproportionate to the limited hazard terrorism presents are neither wise nor responsible.