Illegal Immigration Questions

One of the main groups that helped reelect President Obama was Hispanics. This has led for calls by some for Republicans to rethink their policies on illegal immigration. And rethinking the rhetoric some use on illegal immigration and possibly some policies on the margins should be considered.
But some questions need to be asked. Let's say we grant another amnesty to all illegal immigrants currently in the country. They are now legal. What happens to illegals who come after the amnesty is granted? Would we finally enforce the law? Or would we just let it slide again for several years until to pro-illegal lobby calls for another amnesty? Would we even secure our borders?
We had these promises before the last amnesty. Enforcement was promised. Border security was promised. Both were delayed and then dropped when public attention drifted away.
Wouldn't this just happen again?