NORTH KANSAS CITY, MO. ? Sen. John Kerry, D-Mass., on Saturday accused President Bush of resorting to “character assassination” to discredit critics of the White House’s anti-terrorism strategy and new Medicare law.

Treading cautiously into the latest controversy over Bush’s commitment to fighting al-Qaida before the Sept. 11, 2001, attacks, Kerry also called on national security adviser Condoleezza Rice to testify publicly before the bipartisan commission investigating the deadly terrorist strikes.

“If Condoleezza Rice can find time to do 60 minutes on television before the American people, she ought to find 60 minutes to speak to the commission under oath,” Kerry told reporters. “We are talking about the security of our country.”

Rice has been interviewed privately by commission members, but has refused to talk to them in a public forum.

Rice is scheduled to appear on CBS’ “60 Minutes” today to address allegations by former White House counterterrorism chief Richard Clarke that Bush paid too little attention to al-Qaida before the 2001 attacks and too much to striking Iraq in the aftermath. Clarke, who has contradicted Rice on several points, has aired his concerns in testimony before the Sept. 11 commission, media interviews and a new best-selling book.

Nicolle Devenish, a spokeswoman for the Bush campaign, said Kerry, with his remarks, “seeks to distract Americans from his own failed ideas for protecting America from future attacks.”

Kerry, who pointed reporters to his “new discipline” as a candidate, has remained mostly silent about Clarke’s allegations and the commission’s work over the past week, much of which he spent vacationing in Idaho. The Massachusetts senator, who picked up a copy of Clarke’s book earlier this week, said he has not read or heard much of Clarke’s testimony and cautioned that it would be inappropriate to comment in much detail at this time.

After what many Democrats considered a somewhat bumbling and defensive start to his general election campaign, Kerry has returned from vacation with a new strategy of focusing on economic issues, such as job loss here in North Kansas City, and running a more upbeat and statesmanlike campaign.

A top Kerry aide, who requested anonymity to discuss internal strategy freely, said the Democratic nominee-in-waiting did not want to engage in daily fights with Bush over national security, especially when it is provoked by the president and his allies, and did not want to appear to be politicizing the terrorism investigation. Clarke’s testimony, unless discredited, will damage Bush’s credibility with or without Kerry highlighting it, the aide said.

People ask for autographs and handshakes from Democratic presidential candidate Sen. John Kerry, D-Mass., upon his arrival at the airport in Kansas City, Mo. Kerry criticized President Bush on Saturday for trying to discredit critics of his anti-terrorism strategy and new Medicare law.