MILWAUKEE (Reuters) - Ohio U.S. Senator J.D. Vance, Donald Trump's new running mate, has embraced trade barriers, isolationism and social conservatism, issues that have proven popular with much of Trump's mostly white, working-class base.

Some of those same stances, however, risk turning off moderate voters and major donors, many of whom see his attitude toward corporate America as too combative.

As vice president, Vance will have little formal control over policy decisions, though he could emerge as Trump's heir in 2028 if the former president wins the upcoming election.

Here are Vance's positions on the key issues:

ABORTION

Vance has long been an opponent of abortion rights, though he appears to have softened his position on this issue recently. His current policy preferences appear to be largely in line with those of Trump.

In a 2021 interview, Vance implied that victims of rape and incest should be required to carry pregnancies to term. When Ohioans voted to enshrine abortion rights in their state constitution in 2023, he called it a "gut punch."

Recently, however, Vance has said he opposes federal restrictions on the use of abortion pills. He has also said he believes states should be responsible for abortion-related legislation, a position that Trump shares.

UKRAINE

Vance has been a been a fierce opponent of aid to Ukraine, and he has at times expressed even more skepticism of America's involvement in the conflict than Trump. America's European allies are widely concerned about Vance's selection as Trump's running mate.

Vance has said Ukraine has no chance of regaining all the territory Russia has taken. He has also said that the U.S. should be committing resources instead to other issues, like fortifying the U.S.-Mexico border.

He has also expressed doubt that the war in Ukraine is a major national security concern for the United States. The country should instead be focusing on containing China in the Indo-Pacific region.

Trump had expressed unease about the latest congressional aid package for Ukraine, which was passed in April. But, unlike Vance, he did not explicitly oppose it.

"I don't really care what happens to Ukraine one way or the other," Vance said in an interview in 2022. Trump has said he would solve the conflict in his first day in office, although he has not given many details on how he would do that.

TRADE POLICY

Vance is a consistent proponent of trade barriers, particularly with respect to China. He argues that tariffs are necessary to protect domestic industry from unfair competition abroad.

His position is largely consistent with that of Trump, who has floated a global 10% tariff. Many old-guard Republicans oppose new trade barriers, though the restrictive trade stance of Vance and Trump is now widely popular within the Republican Party.

CORPORATE POWER AND REGULATION

Vance has been critical of corporate America in general and he has even expressed some support for the Biden administration's trust-busting efforts, which is notable given that free market capitalism was until recently a central tenet of Republicanism.

Vance said earlier this year that Federal Trade Commission chair Lina Khan was doing "a pretty good job."

His rhetoric can at times be at odds with that of Trump, who promises to slash regulations on the campaign trail. Still, the former president often rails against corporations that he says attack conservatives or outsource American jobs, meaning there may be less daylight than appears between Vance and Trump when it comes to how they deal with corporate America.

Even though Vance is close to many Silicon Valley donors, he has said that large tech companies have too much influence, a position Trump shares. He has called for Google to be broken up.

While Trump does not appear to have embraced that measure on the trail, he said during his term that Google might face an "antitrust situation" over allegations that it was suppressing conservative views.

MIDDLE EAST

While a steadfast opponent of aid to Ukraine, Vance has consistently stood by Israel. That is consistent with Trump's position, even though the former president initially criticized Israeli leaders for failing to prevent Hamas' attack last October.

Vance has dismissed criticism that Israel has not done enough to avoid harming civilians in Gaza. In the Senate, he helped lead an effort to break apart a bill that provided aid to both Israel and Ukraine. He proposed instead sending aid only to America's ally in the Middle East.

JAN. 6 ATTACK

Vance has consistently downplayed the severity of the Jan. 6, 2021, attack on the U.S. Capitol by Trump supporters, and he has echoed Trump's claims that the Justice Department has been too zealous in prosecuting those who participated in the attack.

He has said he doubts former Vice President Mike Pence's assertion that he was in danger that day, and he has said that unlike Pence, he would not have certified the results of the 2020 election, which Trump lost. Vance has also declined to condemn Trump's attempts to overturn that loss, efforts which led to Trump being indicted on state and federal charges last year.

IMMIGRATION

Like almost all high-profile Republicans, Trump included, Vance says the federal government must flood the U.S.-Mexico border with personnel and resources to stem the flow of immigrants entering the country illegally.

Vance also supports several measures to deter or limit legal immigration. For instance, he has proposed making it harder for immigrants to win asylum claims.

(Reporting by Gram Slattery, editing by Ross Colvin and Alistair Bell)

By Gram Slattery