Paul Little, principal of the City of Glasgow College, said further education was equipped to provide the economy with high-level skills in a cost-effective way.
His comments came during a speech yesterday at a National Tartan Day event at the United States Capitol Building in Washington DC.
Mr Little used the address to set out his vision of what colleges on both sides of the Atlantic should represent in the 21st century.
This is a critical period for colleges in Scotland following cuts to their teaching budgets, staff losses and a drop in the number of students with the axing of part-time courses.
At the same time, the sector has gone through a period of turmoil with a raft of mergers along regional lines.
In contrast, universities have seen funding remain relatively stable, despite the wider cuts to public funding.
Speaking in advance of his address, Mr Little told The Herald: "It is time to challenge the policymakers to reconsider the priority they put on colleges, because the sector is in a very strong position to offer the numbers of professionals urban economies will need in future.
"Colleges already provide a significant proportion of the higher education that is delivered in Scotland, helping students progress to university.
"But we also offer degrees in our own right in a number of disciplines, including the maritime industries, catering and art and design, and there is scope for this to be expanded to include other important niche areas."
Mr Little also stressed that colleges were able to get graduates into the workplace in a quick and cost-effective way.
He said: "We see figures which show debt owed by university students is spiralling, and policy-makers will have to look at different ways of offering higher education in a more cost-effective way.
"College students can enter the workforce more quickly than other routes without accruing significant levels of debt and yet still having the necessary skills."
Michael Russell, the Education Secretary, welcomed Mr Little's contribution.
He said: "Scotland's colleges have a vital role in developing young people to have the right skills and experience for modern employers. This is being done through building closer relationships with communities and business to identify what skills will give student the greatest opportunities to thrive."
Earlier this year a report warned that lecturers at Scottish colleges faced more job losses as the sector copes with cuts and mergers.
A poll of members by sector body Colleges Scotland found half of the country's new regions are predicting future staff cuts. One-third said staffing issues would impact on their ability to deliver courses.
Last year, a report by Audit Scotland found colleges face an 11% reduction in public funding by 2014/15 - amounting to £62 million - with reducing staff numbers "likely to continue to be colleges' main way of delivering savings".
Government funding cuts from 2011 to 2012 have already removed £56m from the sector, with the loss of 800 full-time equivalent staff - most of them lecturers.
National Tartan Day in the US was established in 2008 by the then president George Bush. First Minister Alex Salmond attends the celebrations each year.