The son of a Sikh temple leader slain in a massacre has said he may seek the Congress seat of Republican heavyweight Paul Ryan, calling for a more peaceful America.

Amardeep Kaleka – whose father Satwant Singh Kaleka was credited with saving lives when he fought off a white supremacist in the August 5, 2012 assault in Oak Creek, Wisconsin – said he hoped to decide by November whether to seek the Democratic nomination to challenge Ryan, the Republican vice-presidential candidate last year.

Kaleka hit out at Ryan, chair of the House Budget Committee, over the ongoing shutdown of the federal government in which some 800,000 workers have been furloughed. Republican hardliners have refused to authorize spending without forcing changes in President Barack Obama’s signature reform of expanding health care coverage.

“He’s definitely part of the problem – being the budget chair and having no sway inside your own party to stop something like this from happening – and 800,000 people losing jobs including in his own district, where a number of government services were stopped,” Kaleka told AFP.

“Ultimately, he’s a career politician to me – 13 years in Congress coming out of an internship in DC. He left Wisconsin to go to DC and never really came back,” he said.

Kaleka, a 35-year-old filmmaker, said he met Ryan twice as he pressed for tighter background checks on guns following the massacre at the temple, which killed his father and five other worshipers. The US Senate in April rejected a push supported by Obama to increase background checks for purchases after intense opposition from the gun lobby.

“Responsible people should have guns; people who are irresponsible – or who cannot pass a background check – should not have guns. Easy as that,” Kaleka said.

“I think 90% of the nation agrees, but it’s funny that Congress wouldn’t even pass a bill toward that direction.”

Kaleka said that a more peaceful society would benefit the economy.

“There are so many people who don’t comprehend that peace-building starts with changing our punitive justice system, taking guns out of the wrong people’s hands, and all those affect the economy … as noticed in Europe, where the most peaceful nations are the most economically well-off nations,” he said.