Three things to watch for in JD Vance's convention speech

Ohio Senator JD Vance, Donald Trump's newly minted running mate, will make his national debut on Wednesday as he delivers a prime-time address on the third day of the Republican National Convention in Milwaukee.

At 39, the junior senator and former venture capitalist is the first millennial to join a major party ticket, a youthful contrast to the 78-year-old Trump and the 81-year-old incumbent president, Joe Biden.

As Trump's running mate, Mr Vance is an early favourite for the party's 2028 Republican presidential nomination, but he remains politically unknown to most Americans and many in the party.

Donald Trump Jr, the former president's son and a close friend of Mr Vance, is expected to speak before Mr Vance's wife, Usha Chilukuri Vance, introduces the Republican vice-presidential nominee.

As Mr Vance steps into the national spotlight, here are three things to look out for in his speech.

Mr Vance is expected to highlight his blue-collar background and his family roots in Appalachia as well as Middletown, Ohio, which inspired him to write his 2016 bestselling memoir, Hillbilly Elegy.

The book - which focuses on his impoverished upbringing with a drug-addicted mother in southern Ohio, enlisting as US Marine and later attending Yale Law School - was published as Trump was elected to the White House. Later adapted into an Oscar-nominated film, it was upheld as a glimpse into understanding the white working-class voters that helped fuel Trump's rise.

Republicans are hoping Mr Vance's background will appeal to those voters, especially in Wisconsin, Michigan and Pennsylvania, three battleground states that were key to Trump's 2016 coalition and will be critical for a White House victory in November.

Mr Vance is also expected to highlight his military background. The former Marine, who was deployed to Iraq for six months in 2005, is the first veteran - and the first post-9/11 veteran - to be named to a major party ticket since John McCain in 2008.

Mr Vance's debut follows appearances by former Trump rivals Nikki Haley and Ron DeSantis, who offered their full support for the former president on Tuesday after challenging his candidacy during the Republican primary.

Republicans have sought to close ranks around Trump while Democrats remain divided over whether to proceed with President Biden at the top of their ticket.

The Ohio senator is expected to strike a similar tone of unity, which Trump has said would be an underlying theme of the convention in the wake of an attempt on his life at a rally in Pennsylvania on Saturday. Authorities have yet to determine the motive of the attacker, who was killed at the scene.

In the hours after the shooting, Mr Vance laid blame on President Biden as the country was still learning about the events that unfolded.

"Today is not just some isolated incident," Mr Vance wrote on the platform X, formerly Twitter.

"The central premise of the Biden campaign is that President Donald Trump is an authoritarian fascist who must be stopped at all costs. That rhetoric led directly to President Trump's attempted assassination."

Former Republican Illinois Congressman Adam Kinzinger, a vocal critic of Trump who has endorsed Joe Biden, said Mr Vance's response "should absolutely disqualify" him from the vice-presidential nomination.

Mr Vance is expected to emphasise the message of national unity that his running mate has promised, but so far speakers at the convention have continued heated attacks on the Biden administration and Democrats.

Wednesday's convention theme, "Make America Strong Once Again," is expected to focus on US foreign policy, highlighting the former president's "America First" isolationist policies that reshaped US relationships on the world stage.

Mr Vance has been sharply critical of the Biden administration's foreign policy on issues including the US withdrawal in Afghanistan, the Israel-Gaza war, southern border security and support for Ukraine in its war against Russia.

The nomination of Mr Vance has stoked fears in Europe over the implications of a second Trump presidency for both the Nato alliance and continued US military and financial aid for Ukraine.

The Ohio senator told the Munich Security Conference in February that European countries needed to shoulder a bigger burden so the US could pivot to East Asia against a rising China.

He played a key role in delaying the $60bn (£46bn) military aid package from Washington earlier this year and has suggested that Ukraine should broker a peace deal with Russia, even if that means giving up territory.

But the Republican party remains divided over support for Ukraine and it's unclear if Mr Vance's scepticism of Ukraine aid will influence Trump.

Former UK Prime Minister Boris Johnson, a staunch supporter of Ukraine, traveled to Milwaukee on Tuesday to meet with Trump on continued aid. Following the meeting, he posted on X that he had "no doubt that [Trump] will be strong and decisive in supporting that country and defending democracy".

Concerns about a second Trump presidency rattled stock markets after Trump told Bloomberg Businessweek that Taiwan should have to pay for its own defense.

In response to a question on whether he would defend Taiwan against China, which sees the self-governing island as a breakaway province, the former president said: "You know, we're no different than an insurance company. Taiwan doesn't give us anything."

He also said Taiwan, which is critical to the global chipmaking industry, "took 100% of our chip industry", sending semiconductor stocks tumbling on Wednesday.