WASHINGTON — The upcoming 15th anniversary of the Oklahoma City bombing, which killed 168 people in the nation's worst act of terrorism before 9/11, has prompted renewed concerns about growing anti-government sentiment.

Is the political environment becoming so toxic that we could see another Timothy McVeigh emerge?

Fears that anger could escalate into action beyond the ballot box are not misplaced. Ninety-nine percent of angry Americans might be perfectly satisfied to rail at their television sets — or to show up at a tea party rally — but it takes only one.

The biggest concern for security folks in Washington is the lone operator, the John Hinckley who tries to take out a president for his fantasy girlfriend. Or some variation thereof.

This is why "Don't retreat, reload," Sarah Palin's recent imperative to her tea party audience, felt so off. Obviously, she wasn't suggesting that people arm themselves, as she has explained several times since. Hunting and military vocabulary is hardly new to politics. We "target" audiences or "set our sights" on policies and politicians all the time. In the world of healthy competition, trophies are victories, not dead people.

But words matter, as we never tire of saying. And these are especially sensitive times, given our first African-American president and unavoidable fears about the worst-case scenario. If Jodie Foster could bestir the imagination of Hinckley, a Sarah Palin in the Internet age could move regiments.

Such fears are not unfounded. I hear daily from dissatisfied Americans who feel their duty isn't only to protest, but to fight if necessary. Here is just one recent example, in response to a column I had written about America's true centrist nature:

"Sorry, honey, but we don't need the squishy middle right now. We need the hyper patriots, the combat vets ready to defend the constitution with arms if necessary."

The distance between such thinking and recent examples of overt hostility seems too little. In this space, the unthinkable becomes plausible.

After the health care bill's passage, Democratic congressmen were threatened. The brother of one found his home's gas line cut. At a tea party rally in Washington, some claim there were racial slurs aimed at Georgia Rep. John Lewis, a civil rights hero. Massachusetts Rep. Barney Frank was also targeted, so to speak, with language denigrating to gays.

All of the above have put the nation ill at ease. Add to the mixture of organic anger and grass-roots momentum the heckling language of Beck, Limbaugh and Co., and one fears that volatility could become explosive. What's next, militias?

Well, yes, now that you mention it. In Oklahoma, un-ironic legislators are sympathetic to a proposal to form local voluntary militias to thwart unwanted federal initiatives and to preserve state sovereignty.

"Is it scary? It sure is," tea party leader Al Gerhart told the Associated Press. "But when do the states stop rolling over for the federal government?"

Note to Mr. Gerhart: When their citizens go to the polls.

In more tempered remarks, another Oklahoma tea party leader, J.W. Berry — whose newsletter boasts the motto "Buy more guns, more bullets" — explained that the militia idea isn't "a far-right crazy plan or anything like that. This would be done with the full cooperation of the state Legislature."

Reassured?

Whether we can now boast more wing nuts than in other times is debatable, though hate and vigilante groups, now numbering about 1,000, increased by 54 percent between 2000 and 2008, according to the Southern Poverty Law Center. Anti-immigrant organizations increased last year by almost 80 percent.

What is clear is that technology and social media have empowered the least sane among us and amplified their voices. Thus, a random racist at a tea party rally suddenly becomes the face of a group of people who are, on the whole, decent, law-abiding citizens with legitimate concerns about government expansion and the inherent erosion of individual freedom.

The challenge for all, but especially the media, is to find a balance between vigilance and restraint. How do we expose the unhinged without emboldening them with attention? Inevitably, the lone operator hears his own name summoned from the crowd.

The only palatable answer is what conservatives say they love best — self-control and personal responsibility. When someone spews obscenities, shout them down. When politicians and pundits use inflammatory language, condemn them.

When you choose to remain silent, consider yourself complicit in whatever transpires.

Kathleen Parker is a member of the Washington Post Writers' Group.