WASHINGTON — Senators Clinton and Obama are trading shots over the best way to deal with enemy states, with the former first lady deriding as “irresponsible and frankly naïve” the Illinois lawmaker’s promise to meet with dictators like Fidel Castro and Hugo Chavez.

A day after the diplomacy dispute erupted during Monday’s presidential debate, the jostling for position intensified, with the two leading Democratic campaigns unleashing dueling former senior aides to President Clinton to defend their candidates. Each tried to make the issue a battleground for the competing messages behind his or her candidacy: Mrs. Clinton’s surrogates said her embrace of a more cautious diplomacy demonstrated her experience, while the Obama camp touted his position as embodying the “fresh thinking” he would bring to the White House.

The flap centered on differing responses Mrs. Clinton and Mr. Obama gave to the question of whether they would pledge to meet, during their first year in office and without preconditions, with the leaders of several rogue nations, including, Cuba, Venezuela, Iran, and North Korea. Speaking first, Mr. Obama said he would, while Mrs. Clinton did not, saying she would not “want to be used for propaganda purposes” and would commit only to lower-level meetings to “test the waters” for diplomatic progress. Yesterday morning, Mrs. Clinton turned to a former secretary of state for her husband, Madeleine Albright, who held a conference call with reporters to tout the senator’s answer to the question, saying it was “perfect” and reflected her edge in experience over the other candidates in the race.

“I think she is somebody who is a person who understands how the American presidency works,” Ms. Albright said.

For the Clinton campaign, the goal was also to deepen the perception that Mr. Obama, a first-term senator, is too green for the White House. Aides to Mrs. Clinton released a memo in which the campaign argued that while Mr. Obama had committed to presidential-level meetings with the world’s “worst dictators,” Mrs. Clinton “understands that it is a mistake to commit the power and prestige of America’s presidency years ahead of time by making such a blanket commitment.”

Mrs. Clinton herself went further in an interview with the Quad-City Times of Iowa yesterday, saying Mr. Obama’s statement at the debate was “irresponsible and frankly naïve.”

Mr. Obama and his campaign fought back aggressively. In his own interview with the newspaper, the Illinois senator said what was “irresponsible and naïve” was Mrs. Clinton’s vote in 2002 to authorize the Iraq war, which he opposed. He accused her of flip-flopping on the issue, citing her criticisms of the Bush administration for not talking to Iran or North Korea. “Now she appears to be trying to score political points,” he said.

Mrs. Clinton has repeatedly expressed her willingness to engage with countries like Iran and North Korea, but she has not publicly committed to meeting personally and unconditionally with their leaders in her first year, which the debate question demanded.

The Obama campaign yesterday also released a competing memo, and it issued a statement from its own surrogate from the Clinton administration, a former national security adviser, Anthony Lake. “A great nation and its president should never fear negotiating with anyone and Senator Obama rightly said he would be willing to do so as Richard Nixon did with China and Ronald Reagan did with the Soviet Union,” Mr. Lake said. “After seven years of arrogant refusal to get into direct bargaining with others, surely it’s time for some fresh thinking.”

To combat the experience question further, late in the day the Obama campaign circulated a letter from a group of former top diplomats and Pentagon officials saying Mr. Obama has “the best understanding of how to deal with the complex challenges that America faces in the world.”