The longstanding barriers to the shift from fossil fuels to renewables persist, and manufacturers and developers of the latter can only chip away at them.

I'm talking about the executive order removing longstanding barriers between church and state.

Under the agreement, capital-starved Asian countries agreed to drop longstanding barriers to financial activity by foreign companies.

Meanwhile, Kennedy had achieved some progress in breaking down the longstanding social barriers established over years of HBC hegemony.

Founded in 1991, Mercosur initially stimulated a huge increase in trade among South American nations, as tariff and other longstanding barriers came tumbling down.

The Maritimes were connected to central Canada by the Intercolonial Railway in the 1870s, removing a longstanding barrier to trade.

For biologists, the cloning of animals from adult cells has been a longstanding barrier, but one founded more on practical than theoretical obstacles.

And advocates for the disabled predicted that a successful suit would remove longstanding barriers to such group homes around the nation.

The proposal would break down longstanding barriers between the securities industry and banking and possibly open up ownership of banks to manufacturing companies and others.

A longstanding barrier fell late last year with a discovery by two International Business Machines scientists in Zurich.