NEW YORK/WASHINGTON (Reuters) - U.S. Democratic presidential front-runners Joe Biden and Bernie Sanders have seized on the killing of an Iranian military commander to tout their own leadership as the best antidote to what they call the reckless actions of President Donald Trump.

Biden blamed Trump on Tuesday for an “avoidable” rise in Iranian hostility that he said dated to the Republican president’s decision in 2018 to abandon a nuclear agreement with Iran signed when Biden was vice president.

“I have no illusions about Iran. The regime has long sponsored terrorism and threatened our interests. They’ve ruthlessly killed hundreds of protesters, and they should be held accountable for their actions,” said Biden, speaking in front of five American flags in New York.

“But there is a smart way to counter them - and a self-defeating way. Trump’s approach is demonstrably the latter.”

Sanders, a U.S. senator, has also slammed Trump’s actions but contrasted his own record as an anti-war campaigner with that of Biden, who voted in 2002 to authorize war in Iraq.

Last Friday’s killing of Qassem Soleimani in a U.S. drone strike has intensified U.S.-Iran tensions and raised fears of a wider Middle East war. Trump administration officials have said Soleimani was killed because of solid intelligence indicating forces under his command planned further attacks on U.S. targets in the region, although they have provided no evidence.

Trump campaign spokesman Tim Murtaugh said Democrats risked appearing as apologists for Iran by blaming the United States for responding to “terrorist acts and plans.”

“Americans want to see their president acting decisively and defending the nation’s interests and that’s exactly what President Trump did,” he said.

Reuters/Ipsos polling released on Tuesday found that 53% of U.S. adults disapproved of Trump’s handling of Iran, up 9 percentage points from a similar poll that ran last month.

NATIONAL SECURITY TAKES PROMINENCE

With less than a month until Iowa’s first-in-the-nation caucuses, national security is now dominating the race to take on Trump in the November 2020 election.

The 14 Democrats competing for the nomination have all criticized Trump for the killing of Soleimani. But Biden and Sanders, who come first and second, respectively, in most national opinion polls, both see themselves as the strongest candidate on questions of foreign policy and have spoken repeatedly on Iran since the incident.

Biden aides said they saw a political benefit to putting voters’ focus on his foreign policy experience as a longtime former senator and as No. 2 to President Barack Obama.

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A CNN poll conducted nationwide in November showed 48% of Democratic voters thought Biden was best able to handle foreign policy issues. Sanders was a distant second, with 14% of voters choosing him.

Sanders hopes to appeal to voters fatigued by the long U.S. wars in Afghanistan and Iraq, highlighting his opposition to the 2003 U.S. invasion of Iraq and promising to work in the Senate to avoid a war with Iran.

In Iowa on Friday, he called out Trump for going back on promises he made while campaigning for office in 2016 to end America’s “endless wars.”

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In an interview on CNN on Monday night, Sanders also turned his fire on Biden.

“Joe Biden voted (for) and helped lead the effort for the war in Iraq, the most dangerous foreign policy blunder in the modern history of this country,” Sanders said.

Biden’s long record, including his decision on Iraq as well as his support for international trade deals, meant he would not generate the “energy and excitement” needed for the Democrats to turn out voters and beat Trump in 2020, Sanders added.

Biden has said his vote on Iraq was a mistake, but has defended his foreign policy record. His campaign declined to comment on Sanders’ criticism.