“It’s a free country but I recommend there needs be a limit with guns. Please don’t let people own machine guns or other powerful guns like that. I think there should be a good reason to get a gun. I think there should be a limit about how many guns a person can own.”

-- Letter from Grant, age 8, of Maryland to President Obama calling for gun control in the wake of the Sandy Hook shootings.

Using children to advance a political agenda has long been a dubious tactic.

When adults take children to rallies to hold signs on sensitive topics, it always gives Power Play the willies. What does a 6-year-old know about abortion or gun control or the deficit that he or she wasn’t taught by his or her parents? When a 12-year-old attends an anti-war rally is he or she thinking about just-war theory and global politics or trying to impress an anti-war social studies teacher?

Politicians have always used their children as silent character witnesses in campaign season. Look at the adorable children. Look at the stable nuclear family. This guy/gal can’t be so bad if he/she has a lovely family like that. And family is part of biography, so no big deal.

But when it comes to advancing specific policy points, things get more uncomfortable.

Back in the heyday of the “nuclear freeze” movement during President Reagan’s arms buildup – a movement supported by then Columbia University undergraduate Barack Obama – children were often used to call for the U.S. to take the first step in ending the arms race with the Soviets.

Children, terrified at the thought of a global nuclear holocaust, were deployed at rallies, in movies and on television with the mission of getting Reagan to pull back from his effort to spend the Soviets into oblivion on defense issues.

The conventional wisdom of the time being that the two superpowers would remain locked in global struggle for decades to come, Reagan was depicted as reckless in matching and then outmatching Soviet missile deployments and technology. The conventional wisdom would be proved wrong before the end of the decade, but circa 1983 and “The Day After,” arms race foes had lots of public sentiment on their sides.

At some point, Obama’s adversaries are going to have to start taking him at his word. He means to score complete victories, not make deals in his second term.

Children, then, proved especially good tools for the freezers and those calling for unilateral disarmament. The argument went that children had no say in creating a world gripped by the terror of Mutually Assured Destruction, but would still be incinerated with the more culpable adults.

Plus, they’re cute.

Gun rights supporters are indignant today that President Obama is employing a similar strategy in his call for what would be the broadest-yet gun control measures ever enacted.

Obama will be joined by three schoolchildren, ages 8 to 11, when he issues his call for sweeping gun restrictions and more stringent federal regulations on who can buy firearms.

But pro-gun Americans will have a tough time getting their umbrage to register. After all, Obama is talking about preventing mass shootings in schools, the most recent of which saw 20 children even younger than the ones on display today gunned down.

Even if gun-rights advocates argue that the measures Obama is proposing wouldn’t have prevented the shooting at Sandy Hook, Conn., it is hard to complain too much about kids without sounding just like what gun-control proponents claim the “gun lobby” is: insensitive and indifferent to the real fears of American children.

The truth is that the president has never been in the market for a consensus on gun control or mass shootings. While trotting out children in a call for gun control might be seen as heavy-handed, that’s not going to bother Obama who means to bring a heavy hand against his foes in a second term.

At some point, Obama’s adversaries are going to have to start taking him at his word. He means to score complete victories, not make deals in his second term.

If tugging at heartstrings can keep the pressure on pro-gun Democrats to sign on to a gun ban, Obama will do it -- whatever it takes to achieve the goal of ending gun violence… or to prevent nuclear war, or to curb childhood poverty, etc.

Children of parents who are pro-gun might have written letters to the president calling for armed officers at every school or for tougher mental-health laws, but you will not hear from them today.

Rather than seeming mean by attacking Obama for reading letters from worried children or as a hypocrite for having armed guards at his daughter’s school, pro-gun groups might consider finding some adorable spokespeople of their own.

And Now, A Word From Charles

“If we keep spending like this we will have a president in a few years that will stand up and say we are unable to pay Social Security or the military or benefits, and not because of self-imposed crisis on a debt ceiling but because we will be out of money.”

-- Charles Krauthammer on “Special Report with Bret Baier.”

Chris Stirewalt is digital politics editor for Fox News, and his POWER PLAY column appears Monday-Friday on FoxNews.com. Catch Chris Live online daily at 11:30amET at http:live.foxnews.com.