"Advocating that the FN remains a non-denominational party, Marine Le Pen regularly states her attachment to secularism (laïcité) in French society. She vigorously defends the 1905 French law on the Separation of the Churches and the State, stipulating that the French republic does not recognise, grant a salary to, or subsidise any form of religious worship."
- From her Wikipedia article
Le Pen across much of her platform (pro-abortion, anti-death penalty, anti-iconography) appears to be very much a supporter of secularism. Personally I think she's just taken that stance to the extreme (perhaps as part of the 'de-demonization' of her party). She doesn't want any religious iconography in public, which I think is excessive and difficult to enforce. It's not the government's place to tell people what they should and shouldn't wear, and it certainly isn't its place to send people home or remove their clothing when it doesn't conform to a politician's decrees.
As for the irreconcilability of secularism and Islamic beliefs: every Muslim American I've ever personally interacted with has been just as Western as anyone else. Realistically, the religion is perfectly compatible with Western values if its observers allow the doctrine to modernize. Westerners' perception of Islam is warped by our extensive participation in and media coverage of the war-torn countries where Islam happens to be a majority. This is only natural, as we look to countries where a demographic is the majority in an attempt to understand how they might behave. But if you're looking for a real example of how Muslim and Western values might mix, look at densely-Muslim cities and regions within Western civilization.
For example, in Detroit, Michigan, there is a large Muslim American population whose behavior and attitude is just as American as anyone else's. Muslim people there are motivated and constructive, towards both American institutions and realizing peace among their own religious community.
From my perspective, we have to remember that Islam is a young religion. Formed in the 600's, it has only been around 1400 years. Remember how barbaric Christianity was in 1400 AD? It needs time to modernize, by a mixture of supporting refugees by showing them the value of Western values like tolerance (I know you'll laugh, but it's relative) and allowing the Middle East to work itself out on its own (no more American carpet bombing, please).