U.S. President Joe Biden pledged an "ironclad” commitment to America’s allies Tuesday as he sought to reassure NATO members the United States would not abandon its international obligations despite threats of aggression by Russia and disruption by his all-but-certain fall election rival, former U.S. President Donald Trump.

Hosting Polish political leaders at the White House, Biden made a show of defiance not only against Russian President Vladimir Putin, who continues to wage war on Ukraine, but also — implicitly at least — against Trump, who has said he would "encourage” Russia to attack NATO members that do not spend enough on their militaries.

"When we stand together, no force on earth is more powerful,” Biden said, citing former Secretary of State Madeleine Albright, the Czech-born diplomat who championed NATO membership for Poland, Hungary and her homeland — finalized in March 1999 with the support of Biden, then a senator. "I believed that then, and I believe it now,” he added.